Ok. I think I fixed the bug with the Print Replica format. I sort of overhauled the engine that collates all the various properties of the mobi-type formats. It's a little neater and hopefully won't hang the whole shebang like the old one was doing occasionally (albeit rarely).
I'm going to attach it here as a beta. Give it a workout and see if it's doing what it's intended to do. If I don't hear about any broken functionality or ridiculous bugs after a few days (or so), I'll make it official and update the first post with the new version.
Thanks in advance to any that try it out.
@Tugger: don't forget to reboot your machine after installing if you decide to test out the beta.
[Removed the beta attachment: moved to first post and made "official"]