We'll be needing a new thread for MI2:SE.
Obviously the files are still encrypted on steam right now, and I probably wont be around when the game is first unlocked. So for those who are, this might help. Obviously its only based on assumptions from looking at the encrypted preloaded files:
The Pak file:
It looks a lot smaller than expected - my guess is that its compressed in a similar manner to the xbox version of MI1SE. If thats the case then running XBDecompress on it might do the trick.
Try and have a poke around using Monkey Island Explorer it might work, if the format is the same.
The audio is still in standard wavebanks/soundbanks so its likely that jott's modified UnXwb tool will work just fine. Assuming that everything's in the same format (xwma) then this automated solution might work.
[Edit] See later posts
See this post to extract the music
See this post to browse and extract the .pak