I think Hilmar is right; although I don't think I would call it "more sophisticated", the code below does something similar to yours.

USE cname
oSel = CREATEOBJECT("mySelect")
oSel.Visible = .T.
READ EVENTS

WAIT WINDOW cname+cextra+STR(iid)

DEFINE CLASS mySelect AS Form

	ShowWindow = 1
	WindowType = 0
	Height = 60
	Width = 220
	Caption = "Select Data Folder"
	MaxButton = .F.
	MinButton = .F.

	ADD OBJECT myListbox AS Listbox WITH ;
		Left = 0,;
		Top = 0,;
		Height = 60,;
		Width = 220,;
		ColumnCount = 3,;
		ColumnWidths = '70,64,52',;
		FirstElement = 1,;
		NumberOfElements = 0,;
		RowSource = 'cname,cextra,iid',;
		RowSourceType = 6

	FUNCTION Destroy
		CLEAR EVENTS
	ENDFUNC

ENDDEFINE