@JSWolf - Marvellous, thanks.
I'll give folks another 24 hours to see if anything else comes up and then it will be released. If anyone does notice anything that is related to a particular ePub, please just PM or email me with a link as soon as you do, it saves a whole lot of guessing and time on my part.
As a heads up I am also intending to move all of the posts related to this beta version into the Modify ePub development thread in the Development subforum. I was in two minds about whether to put the beta on that thread in the first place to keep this thread clean, but was worried I might not get enough people seeing it there. It is now 75 posts later, and once I release those posts are of no real interest/relevance to anyone in future browsing this thread, so some cleanout is on the cards.