For anyone else playing an SVN build of 2.3, thought I'd mention that the random UFO crash maps are a little buggy, and if anyone ends up with a map that has stuck or missing aliens, or is otherwise unplayable, I found an easy solution: Go to the options menu screen (as if you were about to abort the mission) and select "retry" and the mission will be re-generated completely, including size of the entire map, what buildings exist where, etc. This way you don't have to go back to your most recent saved game on the geoscape.
I seen a few occasional unplayable tactical missions generated, and a few other weird things, such as a farm barn in the middle of an arctic frozen environment, tiny maps that have no aliens at all (trying to end the turn doesn't work, it's unplayable), etc.
For the most part, the random crash maps work quite well in my experience though.
