Kindle Previewer crashes when turning page

[Jonathan Scott]

I use KindleGen to convert .epub files to .mobi all the time. In fact, I did one book successfully this morning. But my latest project makes Kindle Previewer crash when I try to turn a page. I re-installed Previewer and used it on other books with no problem The crash occurs only when it's in Kindle Fire mode. The book does fine in all the other modes.

ePub Check showed no problems, nor did KindleGen. And I can't find anything in the code that stands out that could be a problem. The book opens, I just can't turn a page without causing Previewer to crash.