The license:
https://www.ubbcentral.com/terms.php?product=UBB.threads

Josh, it also says:
"7. Modifications to the Software. ...
You agree and acknowledge that any alteration or modification of the Software ....(c) may not directly or indirectly be sold, resold, licensed, distributed or otherwise transferred to any third party or parties. This prohibition applies to both altered Infopop™ code and any new code developed by license holders specifically for use with the UBB Software. "

Does this mean all the mods are illegal?