Would be better if your friend would post here personally instead, however.
Tell her to make just a regular map with heightmap and mask, skipping putting those objects into it.
If she tries to export that and it still crashes, it's either something with the game, or the computer itself not being able to take it.
If that succeeds however, it's most likely something with those custom objects of hers or something else they might would have done wrong in the making.
A good thing to try is always to remove EVERYTHING custom made for that map, such as custom meshes, skies, billboards, and similar things. See if it works any better.
I'm sure the crashing could be caused by several things, but it's not easy to know the exact reason since the map maker nevers tells why it crashed.
But since it's the exporting you can just figure it has something to do with creating those .fho .fhm files.
