Lectora HTML publish failing/hanging

I'm encountering problems publishing a rather large course in Lectora Enterprise 9.3. It's about 70 pages, but contains almost 400 PNGs (most around 70K in size but a few in the 300-400K range), maybe 100 MP3 audios, and ten or so FLV videos.

The publisher goes through its normal checks with only the usual warnings about the size of some of the files. However, when I go to publish, the publisher consistently hangs at the same spot -- pretty well along -- in trying to convert one of the MP3s to FLV. By "hangs," I mean that no further files are published, and when I cancel the publish window, I get a Windows error that the process is no longer responding.

There doesn't appear to be anything wrong with that MP3 -- it plays fine via preview, and Flash itself has no problem converting it to FLV. Also, if I delete the page where that file is called, the publisher still hangs in the same general area. I didn't want to completely dismantle the course because of page and object references throughout, but if I hack the course down to about 25% of its size, it will publish successfully.

Has anyone encountered this in publishing large courses? Am I bumping up against some kind of internal memory/limit? Is there some way to troubleshoot the publish process?

Or as a mere user, is my best bet to open a support ticket? Thanks in advance for any wisdom on this.