Havoc,
First of all, congratulations of the big achievement :-))))) I downloaded the released version in the morning, and am still not over the delighted feeling (even though it donsn't look much different from the beta... but I couldn't resist changing the call to gtk_check_version() - you'll see if you update from CVS)...
This damn lightweight vs heavyweight widget dilemma again. I thought we'd initially say "hey we don't care" and say EclipseFixed always has a window (no you can't tell whether you are placing children outside or not... sorry that's how the SWT API is done), and for now live with a little jumpiness - I cared to structure the code such that this decision is localized and we can change it at will without hurting other code. But then I saw the Pixbuf engine and realized any kind of "widget in a widget in a widget" scheme would be visually wrong. Hell, this *does* complicate things. I'll leave it like that for now (so Composites are now heavyweight), but we got to think very hard about it.