[ltk-user] How to access initial toplevel window? (wish window??)

Hi, I'm trying to figure out how to access the initial top-level window... ie. the equivalent of opening wish and typing... . config -bg black I tried this in lisp, (with-ltk () (configure nil :background "darkgreen")) But it didn't seem to work. It gets translated to... NIL configure -background {darkgreen} Hm... I tried other variations where 'nil' was and looked at the code for configure and widget-path but that didn't shed any light. What am I missing? Thanks, Eric