Hey Excel,
A couple of suggestions....
1) in the production version of ubbthreads 5.5, addpost.php doesn't have a ?> at the end. I initially had the calendar working without this, but added it in as a result of a suggestion. Try to just remove it and see if that solves your problem.
2) My version is 1320 lines... did you really delete that many lines?! That sounds weird, you my want to doublecheck.
If the above doesn't solve it, try to figure out whether the problem is specific to your setup: try installing the calendar, as is, and see if it works for you. If it doesn't, let me know the problem. If it does work, then it means that your further changes are causing the problem, and it might help you zero in on what's going on.
Cheers,
Max
