Jeff, the new b24 fixes the UI locking up.
I moved my "problem project" back into
My Albums, and it no longer causes trouble.
RobM and I thought we had ID'ed the issue, but that must have been a red herring. I certainly have been tinkering with image tools (when applied to an RI, for example), so I must have stumbled into the bug you've now fixed.
One of the .info files for the pdf did have a sepia effect listed. Just forgot to mention that.