Sorry about the delay in replying, I've been away for two weeks sans internet. I have no idea at the moment what caused your bug, all I can do at the moment is suggest you keep backups (if the MSE ones aren't enough). The coding for the file moving-around is pretty complicated because I did at one point need to unzip the mse file to get data out (not anymore, thanks to CLI), so I'm hesistant to fiddle with it too much. The whole file management system needs to be rewritten anyway next time I do any serious work on it anyway, to take into account updates in the MSE CLI. Hopefully that will mean inline image loading as well, no long import waits.

I know about the mythic rare problem though, sorry about that. It probably happens on any rarity set to zero, but I haven't tested it much since I intend to rewrite the rarity system too (basically so it imports the rarity system from MSE - theoretically allowing it to support any game later on).

So yeah, erm, the current DwMSE update is that I'm not currently working on it, but its still there on the pile of stuff to do. I've run into a couple of semantic problems regards PlayWithMSE, we'll probably be looking forward to a WithMSE deckbuilder beforehand, but i have by no means given up on it.