The issue still exists. The only difference I saw between your editor config and mine is the setting of the EditCompleteDocument property. I tried setting mine to True but it had no effect.
I didn't see a programmatic setting for RenderItemBorder in your sample, so I'm left to assume it's in your config file?
Here is the placeholder for the dropdown in my custom config file:
<item type="holder" name="variablelist" />
Here is how the dropdown is being instantiated and populated in my custom control:
CuteEditor.Editor richTextBox = new CuteEditor.Editor();
richTextBox.ConfigurationPath = "~/CuteSoft_Client/CuteEditor/Configuration/custom.config";
richTextBox.ThemeType = ThemeType.Office2007;
richTextBox.BreakElement = BreakElement.Br;
richTextBox.EditCompleteDocument = false;
richTextBox.EnableStripScriptTags = false;
richTextBox.AutoParseClasses = false;
Control container = richTextBox.ToolControls[ "variablelist" ].Control;
CuteEditor.RichDropDownList ddl = new CuteEditor.RichDropDownList( richTextBox );
ddl.Items.Add( "Insert Field", "" );
ddl.RichHideFirstItem = true;
ddl.RenderItemBorder = true;
StringDictionary sdict = GetVariableList( var ); // returns dictionary of items from db
foreach ( string name in sdict )
{
ddl.Items.Add( name, sdict[ name ].Value );
}
ddl.Attributes[ "onchange" ] = "CuteEditor_DropDownCommand(this,'PasteHTML')";
container.Controls.Add( ddl );