This map had some of its floors marked as nodraw and some of its spawnflags set to 2 (only drawn on 2nd level). The ramp wasn't working too.
Should be fixed in the attached version of this map.
On the other hand please check:
http://ufoai.ninex.info/wiki/index.php/UFO/Supply_ShipIt says max Capacity of 30. For a ship that has the size of a scout?!?!
Additionally the model doesnt really look like a supply-ship, not even a small one! I would recommend it to be some sort of heavy scout, bomber or a Alien dropship (for short distances) with a troop capacity of MAX 8 Aliens (there is simply not enough storage room inside the ship).
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