I have the same problem... steps to reproduce:
* click on "Move" in a post
* click on the search button, this will open the "Forum Data Lookup" dialog, lookup type = ForumItem
* in the dropdown next to search are the forum groups
* select a forum group (that contains forums) and click go
* result = "no records found"
The strange thing... i have exactly the same problem in the "Tracking Forum" item of "My Settings". I am never able to add forums i want to track there, the only way i am able to track forums is to check the "