help modifying - copy viewport to clipboard

macroScript Copy_Viewport_To_Clipboard
buttontext:"Copy Viewport"
Category:"CG_Tools" 
tooltip:"Copy Viewport To Clipboard" 
(
if setclipboardbitmap != undefined then		--check whether command is undefined... if so then avg not installed or using pre 3ds max 7...
	(
		therender = gw.getViewportDib() 	--new to max 6...
		if therender != undefined do 
			setclipboardbitmap therender	--clipboard access via AVG extension (in version 6 at least)
 
		therender = null
		gc()								--making sure it doesn't sit in memory any longer than needed...
	)
else
	(
		theerrormsg = "This script requires Larry Minton's AVGuard extension. You can download it from scriptspot.com or your favorite max plugin site."
		messagebox theerrormsg title: "AVGuard Extension Not Found"
	)
)