Thanks for making and maintaining this. I have ported the basic idea to a ruby gem here: https://github.com/travis-anderson/rendaku in case anyone wants to use it in a different environment.
I'm having trouble accessing my Dropbox inside BookArt Generator and so is a friend who also uses it. No problem at all accessing it directly on my desktop of phone.
It's just showing me like a site map with the round and round 'cursor' as if it's going to update but it never does.