I finally got around to converting all my tce's to tcz's and discovered that there was a subtle change in ROX with the latest gtk2. When I right-click on a file to use its menu, that file stays highlighted. So when I leave that item, I have to click off it to release it before I can open another file.
I replaced the new glib2 and gtk2 extensions with the old tce versions and the problem went away.
I vaguely recall another discussion about this issue. Is there a resolution other than keeping my tce's?