Great Question! I have been wondering about this also. I guess you could call it an exit/preshow loop; because it plays while one set of guests exits and another set is entering.
I'm assuming several people on here read music, so this might help identify what I assume Horizons is talking about. The most striking part of this loop is the Triplet Theme that is introduced by the strings and repeated in a few spots by the french horns.
I believe the entrance/exit music is an original piece by the composer of the score for the film itself -- unfortunately, I haven't had any luck finding out who that is. Ages ago Randy Thornton indicated that this music had a good chance of appearing on a future official album. Let's hope so!