Your answer is precisely the reason I asked in the first place. You've totally convinced me I'm barking up the wrong tree and I'm now going to look at these X11::GUITest tools.

It even sounds easier.

Thanks very much.

EDIT: Actually, I have made significant progress using this approach. So, thanks again.

EDIT2: OK, I have gotten guitest to do some really neat things. I'm not clear on how to find things in the window. That is, I can poke the windows with a stick, but how do you see them?