Modifying the stock code does violate your license terms to support through the support system at groupee; seeing as you already modify your forums, adding mod's from ubbdev wouldn't push that any further.
The reason for this is, at times, mods will break things, and you can't hold groupee responsible for that...
Keep in mind that 99% of any support queries you'll have will be posted here; and quite frankly, most of us are ubbdev users and could care less if you're stock or not
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