[timrprobocom]

Does using PNGs prevent the black screen issue completely? That is really interesting as it points to a problem in one of the PDF libraries, but users have experienced it using both PDF libraries, which is why I thought the problem was either device specific or in my rendering engine somewhere. I'm looking to switch to a different PDF library, so I'd be curious if that could potentially prevent the black screen issues.

For what it's worth, I have now had 2 instances of the black screen issue using PNGs.  The most recent one was on stage, and came in Act 2 on the closing night of "Beauty and the Beast".  That caused great panic and consternation, but I had gone through rehearsals and 5 previous performances without an issue.

It seems that the problem must be related to a resource shortage.  (Garbage collection delay?)  If I kill the app and restart it every few days, it doesn't happen at all.  Sometimes, I can induce the problem if I scroll quickly forward and backward.  It might be possible to set up an automated test by flipping pages randomly and looking for a big black square in the resulting bitmap.