That is weird that users are unable to edit the original post, yet are able to edit their replies; I don't know of any permission that would affect that.
The only "edit" permission is the "Edit post time limit", but you insist that the groups the user(s) belong to have ample edit time (in minutes).
You're on a fully stock version of UBB.threads, without any major changes to the program or database, correct?
