I have been digging around for known issues on this and so far I have found none. The problem is that when I have a field that is using unlimited as the number of entries and the field resides within an htab from this module the "Add another item" button doesn't work right. Specifically it runs the JS and gets nothing back. It looks like it is having trouble identifying the triggering element properly.
I hope I am missing a known bugfix. But if not, here is a great new problem. I am still working on what is going on, but my knowledge of how drupal handles all of these fields in the backend is still a bit underdeveloped. Since I am a programmer I know I will find a solution eventually. But I would be surprised if this problem has not been noticed by others.