Regarding the licensing issue. Let me put it this way.
Who would be idiotic enough to use v3.9Qa? Seriously. If you don't have a legit license for UBB, HOW could you use UBB 6.xx let alone v4.0.0 legally besides using an illegal version? UBBDev is a resource for LEGIT UBB users, not warez UBB users.
However, to answer your question. As you state, there is nothing inside that document that states that outside distribution of the hack is not permitted. Therefore, in a legal sense of the word, you're allowed to distribute it if you like although that's certainly not what I want, that is technically allowed.
Further versions of Who's Online (in particular v4.1.0) will clarify more on this.
Hope this clarifies it for you. LMK if you have any more questions or the like.
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