I think the reason Sindol was talking about scripting was to point out that character feats that aren't in the game would have to be cheesed, and the Avlis staff doesn't want to get into regulating that. For example, with Tongue of the Sun and Moon, it would be tough for the DMs to keep track of which characters are monks and of those, which are of sufficient level to have that feat, and then monitor conversations to see which characters behave properly. I'm sure that wasn't what you had in mind anyway, but basically, if the team can't regulate something, they won't post a ruling on it.
A somewhat related example, is (rarely) you'll see folks with characters typing something along the lines of /dwarvish/ and then dialog to simulate their character speaking in the dwarvish language. This is also cheesing, but in general a good kind, and folks are usually willing to keep in the spirit of role-play - some folks play as if they don't understand it, and some do. But I doubt the staff would try to force people to react to that type of dialog one way or another and would leave it up to the players to work it out. I'd suggest you work with the feat "Tongue of the Sun and Moon" in a similar way. Once your monk is high enough level, and you think he should be able to understand everything, I'd feel free to let him understand all the text that appears around him. I've also seen quite a few rangers and druids use "animal messengers" for in-game tells and out-of-game PMs - another bit of harmless cheesing that adds some flavor, and would also be in line for monks with that feat. But like I said, it's a kind of cheesing, and certainly players aren't forced to ignore dialog they see around them, and I don't be surprised if the staff does not make an official statement as to whether or not monks have that ability.
The other feats stray into a different catagory - cheesy things that would be expected to actually affect game-play. A dimension-door-like ability would allow your monk to get out of combat situations, for example, that the NWN engine wouldn't allow. We all do this from time to time with simple things, like *I tie the unconcious bandit's hands behind his back*, and generally everyone will play along with that. A good guideline to follow is that if you're trying to cheese a standard action that anyone could do, it's probably okay to do it (like example above). But if it's an action that's extraordinary, expecially if it requires fairly intimate knowledge of D&D rules that aren't present in NWN, then I wouldn't do it. It'd be too easy for other folks to declare abilities that have no basis in rules, and with the abundance of D&D rules out there, it would be way too much work for DMs to enforce.
Now, if you could encode a good teleport...
Just my (really long-winded) two cents.