21:
How do I get the caption of the cell/item from the point

// MouseMove event - Occurs when the user moves the mouse.
private void axExplorerTree1_MouseMoveEvent(object sender, AxEXPLORERTREELib._IExplorerTreeEvents_MouseMoveEvent e)
{
	Object var_Object = (axExplorerTree1.get_GroupListFromPoint(-1,-1) as Object);
}
//this.axExplorerTree1.MouseMoveEvent += new AxEXPLORERTREELib._IExplorerTreeEvents_MouseMoveEventHandler(this.axExplorerTree1_MouseMoveEvent);

axExplorerTree1.BeginUpdate();
EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Group 1");
	var_Group.HeaderVisible = true;
	var_Group.Columns.Clear();
	var_Group.Columns.Add("Number");
	(var_Group.Columns.Add("Round") as EXPLORERTREELib.Column).ComputedField = "round(%0)";
	EXPLORERTREELib.Items var_Items = var_Group.Items;
		var_Items.AddItem("-1.98");
		var_Items.AddItem("0.99");
		var_Items.AddItem("1.23");
		var_Items.AddItem("2.34");
	var_Group.Expanded = true;
EXPLORERTREELib.Group var_Group1 = axExplorerTree1.Groups.Add("Group 2");
	var_Group1.HeaderVisible = true;
	var_Group1.Columns.Clear();
	var_Group1.Columns.Add("Number");
	(var_Group1.Columns.Add("Round") as EXPLORERTREELib.Column).ComputedField = "round(%0)";
	EXPLORERTREELib.Items var_Items1 = var_Group1.Items;
		var_Items1.AddItem("-1.98");
		var_Items1.AddItem("0.99");
		var_Items1.AddItem("1.23");
		var_Items1.AddItem("2.34");
	var_Group1.Expanded = true;
axExplorerTree1.EndUpdate();

20:
How can I ensure that a specified item is visible

axExplorerTree1.BeginUpdate();
EXPLORERTREELib.Groups var_Groups = axExplorerTree1.Groups;
	EXPLORERTREELib.Group var_Group = var_Groups.Add("Group");
		var_Group.Expanded = true;
		EXPLORERTREELib.Items var_Items = var_Group.Items;
			var_Items.AddItem("Item");
			var_Items.AddItem("Item");
			var_Items.AddItem("Item");
			var_Items.AddItem("Item");
		var_Group.PutItems(var_Group.GetItems(0),0);
		var_Group.PutItems(var_Group.GetItems(0),0);
		var_Group.Items.AddItem("Ensure");
EXPLORERTREELib.Items var_Items1 = axExplorerTree1.Groups[0].Items;
	int h = var_Items1[16];
	var_Items1.set_ItemBackColor(h,(uint)ColorTranslator.ToWin32(Color.FromArgb(255,255,0)));
	var_Items1.EnsureVisibleItem(h);
axExplorerTree1.EndUpdate();

19:
is it possible to display icons in the control's shortcut bar

axExplorerTree1.BeginUpdate();
axExplorerTree1.Images("gBJJgBAIDAAGAAEAAQhYAf8Pf4hh0QihCJo2AEZjQAjEZFEaIEaEEaAIAkcbk0olUrlktl0vmExmUzmk1m03nE5nU7nk9n0/oFBoVDolFo1HpFJpVLplNp1PqFRqVTq" +
"lVq1XrFZrVbrldr1fsFhsVjslls1ntFptVrtltt1vuFxuVzul1u13vF5vV7vl9v1/wGBwWDwmFw2HxGJxWLxmNx0xiFdyOTh8Tf9ZymXx+QytcyNgz8r0OblWjyWds+m" +
"0ka1Vf1ta1+r1mos2xrG2xeZ0+a0W0qOx3GO4NV3WeyvD2XJ5XL5nN51aiw+lfSj0gkUkAEllHanHI5j/cHg8EZf7w8vl8j4f/qfEZeB09/vjLAB30+kZQAP/P5/H6/y" +
"NAOAEAwCjMBwFAEDwJBMDwLBYAP2/8Hv8/gAGAD8LQs9w/nhDY/oygIA=");
axExplorerTree1.ShowShortcutBar = true;
EXPLORERTREELib.Groups var_Groups = axExplorerTree1.Groups;
	var_Groups.Add("Group A.1").Shortcut = "<img>1</img> First Group";
	var_Groups.Add("Group A.2").Shortcut = "<img>1</img> First Group";
	var_Groups.Add("Group B.1").Shortcut = "<img>2</img> Second Group";
	var_Groups.Add("Group B.2").Shortcut = "<img>2</img> Second Group";
	var_Groups.Add("Group B.3").Shortcut = "<img>2</img> Second Group";
axExplorerTree1.EndUpdate();

18:
How can I display the control's shortcut bar

axExplorerTree1.BeginUpdate();
axExplorerTree1.ShowShortcutBar = true;
EXPLORERTREELib.Groups var_Groups = axExplorerTree1.Groups;
	var_Groups.Add("Group A.1").Shortcut = "A";
	var_Groups.Add("Group A.2").Shortcut = "A";
	var_Groups.Add("Group B.1").Shortcut = "B";
	var_Groups.Add("Group B.2").Shortcut = "B";
	var_Groups.Add("Group B.3").Shortcut = "B";
axExplorerTree1.EndUpdate();

17:
Can I display the cell's check box after the text

axExplorerTree1.BeginUpdate();
EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Default");
	var_Group.Expanded = true;
	EXPLORERTREELib.Column var_Column = var_Group.Columns[0];
		var_Column.set_Def(EXPLORERTREELib.DefColumnEnum.exCellHasCheckBox,true);
		var_Column.set_Def(EXPLORERTREELib.DefColumnEnum.exCellDrawPartsOrder,"caption,check");
	EXPLORERTREELib.Items var_Items = var_Group.Items;
		var_Items.set_CellHasCheckBox(var_Items.AddItem("Caption 1"),0,true);
		var_Items.set_CellHasCheckBox(var_Items.AddItem("Caption 2"),0,true);
axExplorerTree1.EndUpdate();

16:
Can I change the order of the parts in the cell, as checkbox after the text, and so on

axExplorerTree1.Images("gBJJgBAIDAAGAAEAAQhYAf8Pf4hh0QihCJo2AEZjQAjEZFEaIEaEEaAIAkcbk0olUrlktl0vmExmUzmk1m03nE5nU7nk9n0/oFBoVDolFo1HpFJpVLplNp1PqFRqVTq" +
"lVq1XrFZrVbrldr1fsFhsVjslls1ntFptVrtltt1vuFxuVzul1u13vF5vV7vl9v1/wGBwWDwmFw2HxGJxWLxmNx0xiFdyOTh8Tf9ZymXx+QytcyNgz8r0OblWjyWds+m" +
"0ka1Vf1ta1+r1mos2xrG2xeZ0+a0W0qOx3GO4NV3WeyvD2XJ5XL5nN51aiw+lfSj0gkUkAEllHanHI5j/cHg8EZf7w8vl8j4f/qfEZeB09/vjLAB30+kZQAP/P5/H6/y" +
"NAOAEAwCjMBwFAEDwJBMDwLBYAP2/8Hv8/gAGAD8LQs9w/nhDY/oygIA=");
axExplorerTree1.BeginUpdate();
EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Default");
	var_Group.Expanded = true;
	var_Group.Columns[0].set_Def(EXPLORERTREELib.DefColumnEnum.exCellDrawPartsOrder,"caption,check,icon,icons,picture");
	EXPLORERTREELib.Items var_Items = var_Group.Items;
		int h = var_Items.AddItem("Text");
		var_Items.set_CellImage(h,0,1);
		var_Items.set_CellHasCheckBox(h,0,true);
axExplorerTree1.EndUpdate();

15:
Can I have an image displayed after the text. Can I get that effect without using HTML content

axExplorerTree1.Images("gBJJgBAIDAAGAAEAAQhYAf8Pf4hh0QihCJo2AEZjQAjEZFEaIEaEEaAIAkcbk0olUrlktl0vmExmUzmk1m03nE5nU7nk9n0/oFBoVDolFo1HpFJpVLplNp1PqFRqVTq" +
"lVq1XrFZrVbrldr1fsFhsVjslls1ntFptVrtltt1vuFxuVzul1u13vF5vV7vl9v1/wGBwWDwmFw2HxGJxWLxmNx0xiFdyOTh8Tf9ZymXx+QytcyNgz8r0OblWjyWds+m" +
"0ka1Vf1ta1+r1mos2xrG2xeZ0+a0W0qOx3GO4NV3WeyvD2XJ5XL5nN51aiw+lfSj0gkUkAEllHanHI5j/cHg8EZf7w8vl8j4f/qfEZeB09/vjLAB30+kZQAP/P5/H6/y" +
"NAOAEAwCjMBwFAEDwJBMDwLBYAP2/8Hv8/gAGAD8LQs9w/nhDY/oygIA=");
axExplorerTree1.BeginUpdate();
EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Default");
	var_Group.Expanded = true;
	var_Group.Columns[0].set_Def(EXPLORERTREELib.DefColumnEnum.exCellDrawPartsOrder,"caption,icon,check,icons,picture");
	EXPLORERTREELib.Items var_Items = var_Group.Items;
		int h = var_Items.AddItem("Text");
		var_Items.set_CellImage(h,0,1);
axExplorerTree1.EndUpdate();

14:
How do I enable the filter prompt feature

axExplorerTree1.BeginUpdate();
axExplorerTree1.Groups.Add("Group 1");
EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Group 2");
	var_Group.AutoHeight = true;
	var_Group.HeaderVisible = true;
	var_Group.Columns.Clear();
	var_Group.ColumnAutoResize = true;
	var_Group.ContinueColumnScroll = false;
	var_Group.MarkSearchColumn = false;
	var_Group.SearchColumnIndex = 1;
	var_Group.FilterBarPromptVisible = true;
	EXPLORERTREELib.Columns var_Columns = var_Group.Columns;
		(var_Columns.Add("Name") as EXPLORERTREELib.Column).Width = 96;
		(var_Columns.Add("Title") as EXPLORERTREELib.Column).Width = 96;
		var_Columns.Add("City");
	EXPLORERTREELib.Items var_Items = var_Group.Items;
		int h0 = var_Items.AddItem("Nancy Davolio");
		var_Items.set_CellCaption(h0,1,"Sales Representative");
		var_Items.set_CellCaption(h0,2,"Seattle");
		h0 = var_Items.AddItem("Andrew Fuller");
		var_Items.set_CellCaption(h0,1,"Vice President, Sales");
		var_Items.set_CellCaption(h0,2,"Tacoma");
		var_Items.set_SelectItem(h0,true);
		h0 = var_Items.AddItem("Janet Leverling");
		var_Items.set_CellCaption(h0,1,"Sales Representative");
		var_Items.set_CellCaption(h0,2,"Kirkland");
		h0 = var_Items.AddItem("Margaret Peacock");
		var_Items.set_CellCaption(h0,1,"Sales Representative");
		var_Items.set_CellCaption(h0,2,"Redmond");
		h0 = var_Items.AddItem("Steven Buchanan");
		var_Items.set_CellCaption(h0,1,"Sales Manager");
		var_Items.set_CellCaption(h0,2,"London");
		h0 = var_Items.AddItem("Michael Suyama");
		var_Items.set_CellCaption(h0,1,"Sales Representative");
		var_Items.set_CellCaption(h0,2,"London");
		h0 = var_Items.AddItem("Robert King");
		var_Items.set_CellCaption(h0,1,"Sales Representative");
		var_Items.set_CellCaption(h0,2,"London");
		h0 = var_Items.AddItem("Laura Callahan");
		var_Items.set_CellCaption(h0,1,"Inside Sales Coordinator");
		var_Items.set_CellCaption(h0,2,"Seattle");
		h0 = var_Items.AddItem("Anne Dodsworth");
		var_Items.set_CellCaption(h0,1,"Sales Representative");
		var_Items.set_CellCaption(h0,2,"London");
	var_Group.Expanded = true;
axExplorerTree1.Groups.Add("Group 3");
axExplorerTree1.EndUpdate();

13:
Can I specify unsortable items

axExplorerTree1.BeginUpdate();
EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Default");
	var_Group.AutoHeight = true;
	var_Group.HeaderVisible = true;
	var_Group.Columns.Clear();
	var_Group.HasLines = EXPLORERTREELib.HierarchyLineEnum.exNoLine;
	var_Group.ScrollBySingleLine = true;
	var_Group.MarkSearchColumn = false;
	EXPLORERTREELib.Columns var_Columns = var_Group.Columns;
		var_Columns.Add("Name");
		var_Columns.Add("A");
		var_Columns.Add("B");
		var_Columns.Add("C");
	EXPLORERTREELib.Items var_Items = var_Group.Items;
		int h = var_Items.AddItem("Group 1");
		var_Items.set_CellHAlignment(h,0,EXPLORERTREELib.AlignmentEnum.CenterAlignment);
		var_Items.set_ItemDivider(h,0);
		var_Items.set_ItemDividerLineAlignment(h,EXPLORERTREELib.DividerAlignmentEnum.DividerBoth);
		var_Items.set_ItemHeight(h,24);
		var_Items.set_SortableItem(h,false);
		int h1 = var_Items.InsertItem(h,null,"Child 1");
		var_Items.set_CellCaption(h1,1,1);
		var_Items.set_CellCaption(h1,2,2);
		var_Items.set_CellCaption(h1,3,3);
		h1 = var_Items.InsertItem(h,null,"Child 2");
		var_Items.set_CellCaption(h1,1,4);
		var_Items.set_CellCaption(h1,2,5);
		var_Items.set_CellCaption(h1,3,6);
		var_Items.set_ExpandItem(h,true);
		h = var_Items.AddItem("Group 2");
		var_Items.set_CellHAlignment(h,0,EXPLORERTREELib.AlignmentEnum.CenterAlignment);
		var_Items.set_ItemDivider(h,0);
		var_Items.set_ItemDividerLineAlignment(h,EXPLORERTREELib.DividerAlignmentEnum.DividerBoth);
		var_Items.set_ItemHeight(h,24);
		var_Items.set_SortableItem(h,false);
		h1 = var_Items.InsertItem(h,null,"Child 1");
		var_Items.set_CellCaption(h1,1,1);
		var_Items.set_CellCaption(h1,2,2);
		var_Items.set_CellCaption(h1,3,3);
		h1 = var_Items.InsertItem(h,null,"Child 2");
		var_Items.set_CellCaption(h1,1,4);
		var_Items.set_CellCaption(h1,2,5);
		var_Items.set_CellCaption(h1,3,6);
		var_Items.set_ExpandItem(h,true);
	var_Group.Expanded = true;
axExplorerTree1.EndUpdate();

12:
Can I change the style of the line being displayed by a divider item

axExplorerTree1.BeginUpdate();
EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Default");
	var_Group.HeaderVisible = true;
	var_Group.Columns.Clear();
	var_Group.MarkSearchColumn = false;
	var_Group.TreeColumnIndex = -1;
	var_Group.ScrollBySingleLine = false;
	var_Group.Columns.Add("C1");
	var_Group.Columns.Add("C2");
	var_Group.SelBackMode = EXPLORERTREELib.BackModeEnum.exTransparent;
	EXPLORERTREELib.Items var_Items = var_Group.Items;
		int h = var_Items.AddItem("Cell 1");
		var_Items.set_CellCaption(h,1,"This is bit of text that's shown on multiple lines. This is bit of text that's shown on multiple lines.");
		var_Items.set_CellSingleLine(h,1,false);
		h = var_Items.AddItem("This is bit of text that's displayed on the entire item, divider.");
		var_Items.set_ItemDivider(h,0);
		var_Items.set_ItemDividerLine(h,EXPLORERTREELib.DividerLineEnum.DoubleDotLine);
		var_Items.set_ItemDividerLineAlignment(h,EXPLORERTREELib.DividerAlignmentEnum.DividerBoth);
		var_Items.set_CellHAlignment(h,0,EXPLORERTREELib.AlignmentEnum.CenterAlignment);
		var_Items.set_ItemHeight(h,24);
	var_Group.Expanded = true;
axExplorerTree1.EndUpdate();

11:
How can I expand all items

axExplorerTree1.BeginUpdate();
EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Default");
	var_Group.HeaderVisible = true;
	var_Group.Columns.Clear();
	var_Group.LinesAtRoot = EXPLORERTREELib.LinesAtRootEnum.exLinesAtRoot;
	var_Group.Columns.Add("Items");
	EXPLORERTREELib.Items var_Items = var_Group.Items;
		int h = var_Items.AddItem("Root 1");
		var_Items.InsertItem(h,null,"Child 1");
		var_Items.InsertItem(h,null,"Child 2");
		h = var_Items.AddItem("Root 2");
		var_Items.InsertItem(h,null,"Child 1");
		var_Items.InsertItem(h,null,"Child 2");
		var_Items.set_ExpandItem(0,true);
	var_Group.Expanded = true;
axExplorerTree1.EndUpdate();

10:
Is it possible display numbers in the same format no matter of regional settings in the control panel

EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Default");
	var_Group.HeaderVisible = true;
	var_Group.Columns.Clear();
	(var_Group.Columns.Add("Def") as EXPLORERTREELib.Column).set_Def(EXPLORERTREELib.DefColumnEnum.exCellCaptionFormat,1);
	EXPLORERTREELib.Items var_Items = var_Group.Items;
		int h = var_Items.AddItem(100000.27);
		var_Items.set_FormatCell(h,0,"(value format '') +  ' <fgcolor=808080>(default positive)'");
		h = var_Items.AddItem(100000.27);
		var_Items.set_FormatCell(h,0,"(value format '2|.|3|,|1|1')");
		h = var_Items.AddItem(-100000.27);
		var_Items.set_FormatCell(h,0,"(value format '') +  ' <fgcolor=808080>(default negative)'");
		h = var_Items.AddItem(-100000.27);
		var_Items.set_FormatCell(h,0,"(value format '2|.|3|,|1|1')");
	var_Group.Expanded = true;

9:
Is it possible to format numbers

axExplorerTree1.BeginUpdate();
EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Default");
	var_Group.HeaderVisible = true;
	var_Group.MarkSearchColumn = false;
	var_Group.Columns.Clear();
	EXPLORERTREELib.Columns var_Columns = var_Group.Columns;
		var_Columns.Add("Name");
		EXPLORERTREELib.Column var_Column = (var_Columns.Add("A") as EXPLORERTREELib.Column);
			var_Column.SortType = EXPLORERTREELib.SortTypeEnum.SortNumeric;
			var_Column.AllowSizing = false;
			var_Column.Width = 36;
			var_Column.FormatColumn = "len(value) ? value + ' +'";
		EXPLORERTREELib.Column var_Column1 = (var_Columns.Add("B") as EXPLORERTREELib.Column);
			var_Column1.SortType = EXPLORERTREELib.SortTypeEnum.SortNumeric;
			var_Column1.AllowSizing = false;
			var_Column1.Width = 36;
			var_Column1.FormatColumn = "len(value) ? value + ' +'";
		EXPLORERTREELib.Column var_Column2 = (var_Columns.Add("C") as EXPLORERTREELib.Column);
			var_Column2.SortType = EXPLORERTREELib.SortTypeEnum.SortNumeric;
			var_Column2.AllowSizing = false;
			var_Column2.Width = 36;
			var_Column2.FormatColumn = "len(value) ? value + ' ='";
		EXPLORERTREELib.Column var_Column3 = (var_Columns.Add("A+B+C") as EXPLORERTREELib.Column);
			var_Column3.SortType = EXPLORERTREELib.SortTypeEnum.SortNumeric;
			var_Column3.Width = 64;
			var_Column3.ComputedField = "dbl(%1)+dbl(%2)+dbl(%3)";
			var_Column3.FormatColumn = "type(value) in (0,1) ? 'null' : ( dbl(value)<0 ? '<fgcolor=FF0000>'+ (value format '2|.|3|,|1' ) : (dbl(value)>0 ? '<fgcolor=00" +
"00FF>+'+(value format '2|.|3|,' ): '0.00') )";
			var_Column3.set_Def(EXPLORERTREELib.DefColumnEnum.exCellCaptionFormat,1);
	EXPLORERTREELib.Items var_Items = var_Group.Items;
		int h = var_Items.AddItem("Root");
		var_Items.set_CellCaptionFormat(h,4,EXPLORERTREELib.CaptionFormatEnum.exComputedField);
		int h1 = var_Items.InsertItem(h,null,"Child 1");
		var_Items.set_CellCaption(h1,1,7);
		var_Items.set_CellCaption(h1,2,3);
		var_Items.set_CellCaption(h1,3,1);
		h1 = var_Items.InsertItem(h,null,"Child 2");
		var_Items.set_CellCaption(h1,1,-2);
		var_Items.set_CellCaption(h1,2,-2);
		var_Items.set_CellCaption(h1,3,-4);
		h1 = var_Items.InsertItem(h,null,"Child 3");
		var_Items.set_CellCaption(h1,1,2);
		var_Items.set_CellCaption(h1,2,2);
		var_Items.set_CellCaption(h1,3,-4);
		var_Items.set_ExpandItem(h,true);
	var_Group.Expanded = true;
axExplorerTree1.EndUpdate();

8:
Is there any function to round the values base on the .5 value

EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Default");
	var_Group.HeaderVisible = true;
	var_Group.Columns.Clear();
	var_Group.Columns.Add("Number");
	(var_Group.Columns.Add("Round") as EXPLORERTREELib.Column).ComputedField = "round(%0)";
	EXPLORERTREELib.Items var_Items = var_Group.Items;
		var_Items.AddItem("-1.98");
		var_Items.AddItem("0.99");
		var_Items.AddItem("1.23");
		var_Items.AddItem("2.34");
	var_Group.Expanded = true;

7:
How can I show a column that adds values in the cells

EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Default");
	var_Group.Columns.Clear();
	var_Group.HeaderVisible = true;
	var_Group.Columns.Add("A");
	var_Group.Columns.Add("B");
	(var_Group.Columns.Add("A+B") as EXPLORERTREELib.Column).ComputedField = "dbl(%0) + dbl(%1)";
	EXPLORERTREELib.Items var_Items = var_Group.Items;
		var_Items.set_CellCaption(var_Items.AddItem(1),1,2);
	EXPLORERTREELib.Items var_Items1 = var_Group.Items;
		var_Items1.set_CellCaption(var_Items1.AddItem(10),1,20);
	var_Group.Expanded = true;

6:
How do I change the item's background color for numbers less than a value

EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Default");
	var_Group.ConditionalFormats.Add("dbl(%0) < 10",null).BackColor = (uint)ColorTranslator.ToWin32(Color.FromArgb(255,0,0));
	var_Group.Items.AddItem(1);
	var_Group.Items.AddItem(2);
	var_Group.Items.AddItem(10);
	var_Group.Items.AddItem(20);
	var_Group.Expanded = true;

5:
How do I highlight in bold the numbers greater than a value

EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Default");
	var_Group.ConditionalFormats.Add("dbl(%0) >= 10",null).Bold = true;
	var_Group.Items.AddItem(1);
	var_Group.Items.AddItem(2);
	var_Group.Items.AddItem(10);
	var_Group.Items.AddItem(20);
	var_Group.Expanded = true;

4:
How do I change the caption being displayed in the control's filter bar

EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Default");
	var_Group.FilterBarCaption = "your filter caption";
	EXPLORERTREELib.Column var_Column = (var_Group.Columns.Add("Column") as EXPLORERTREELib.Column);
		var_Column.DisplayFilterButton = true;
		var_Column.FilterType = EXPLORERTREELib.FilterTypeEnum.exBlanks;
	var_Group.ApplyFilter();
	var_Group.Expanded = true;

3:
Is it possible to change the style for the vertical or horizontal grid lines, in the list area

axExplorerTree1.BeginUpdate();
EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Default");
	var_Group.AutoHeight = true;
	var_Group.DrawGridLines = EXPLORERTREELib.GridLinesEnum.exAllLines;
	var_Group.GridLineStyle = EXPLORERTREELib.GridLinesStyleEnum.exGridLinesVSolid | EXPLORERTREELib.GridLinesStyleEnum.exGridLinesHDot4;
	var_Group.ColumnAutoResize = false;
	EXPLORERTREELib.Column var_Column = var_Group.Columns[0];
		var_Column.Caption = "C1";
		var_Column.Width = 64;
	var_Group.Columns.Add("C2");
	var_Group.Columns.Add("C3");
	var_Group.ColumnAutoResize = true;
	EXPLORERTREELib.Items var_Items = var_Group.Items;
		int h = var_Items.AddItem("Item 1");
		var_Items.set_CellCaption(h,1,"SubItem 1.2");
		var_Items.set_CellCaption(h,2,"SubItem 1.3");
		h = var_Items.AddItem("Item 2");
		var_Items.set_CellCaption(h,1,"SubItem 2.2");
		var_Items.set_CellCaption(h,2,"SubItem 2.3");
		h = var_Items.AddItem("Item 3");
		var_Items.set_CellCaption(h,1,"SubItem 3.2");
		var_Items.set_CellCaption(h,2,"SubItem 3.3");
	var_Group.Expanded = true;
axExplorerTree1.EndUpdate();

2:
Is it possible to change the style for the grid lines, for instance to be solid not dotted

axExplorerTree1.BeginUpdate();
EXPLORERTREELib.Group var_Group = axExplorerTree1.Groups.Add("Default");
	var_Group.DrawGridLines = EXPLORERTREELib.GridLinesEnum.exAllLines;
	var_Group.GridLineStyle = EXPLORERTREELib.GridLinesStyleEnum.exGridLinesSolid;
	var_Group.Expanded = true;
axExplorerTree1.EndUpdate();

1:
How can I change the visual appearance for the groups, using your EBN files

axExplorerTree1.BeginUpdate();
axExplorerTree1.VisualAppearance.Add(1,"c:\\exontrol\\images\\normal.ebn");
(axExplorerTree1.GetOcx() as EXPLORERTREELib.ExplorerTree).BackColorGroup = 0x1000000;
EXPLORERTREELib.Groups var_Groups = axExplorerTree1.Groups;
	var_Groups.Add("Group 1");
	var_Groups.Add("Group 2");
	var_Groups.Add("Group 3");
axExplorerTree1.EndUpdate();