Yeah, retail key most likely won't work. The original publisher would need to provide Stardock with the key database to validate the retail keys, and at least so far none of them wanted to do it. I wouldn't expect any agreement reached with NWN's publisher to be any different, at this point.

I wish this game would be made available on Impuse as well. I'd buy it immediately.

Just as an FYI, we generally can't talk about titles coming to Impulse until there's a contract signed.  So a lack of a response when someone asks "How about you get game X?" isn't us ignoring the forum, it's just that we can't comment on whether or not a game is upcoming.  Only once we have a definitive answer such as "Yes, it's coming" or "No, that title won't be on Impulse" THEN we can answer questions.

We see requests for games, and do pursue them when posted, so keep asking for games you want to see available on Impulse!  We may just be a bit quiet until we can give firm news.

As a side note: We offer all publishers and developers we partner with on Impulse the option of integrating their retail keys with Impulse.  So far none have taken us up on the offer.