not receiving mouse release events

[Chuck Crisler <charles crisler comcast net>]

I have an app that has two windows. The top window has a gtk scrolled
window with an embedded tree control and the bottom has a scrolled
window with some display object. I have tried a viewport (clearly
wrong), a drawing area and a layout (at different times). The problem is
that the bottom window receives mouse button press events but not
release or motion events. The intent is to allow users to select items
in the lower window to expand them or scroll around. I have used
gtkparasite to confirm that the lower scrolled window has the button
release event mask (actually, it has all masks). I know that I am doing
something wrong. Any ideas or approaches to figure out where I have
screwed up?

TIA,
Chuck