Twice now I've attempted to run this mod with two different people who had no familiarity with it, and both times now, whenever we go through Two Betrayals, the game bugs out, specifically at the point we return to the Control Room to aid the Marines against the Flood. When this happens, half the sound effects in the game stop playing and some of the level geometry just plain doesn't load in afterwards. I've never had this issue occur to me playing alone, though.

Has anybody else experienced this issue?