those crashes are not random. they always occur at Tessalting Surfaces.
The jokes on me here, since i deactivated tesselation. i tried to build a simple map, that works sometimes, sometimes it crashes when building lights.
acoording to windows, the error is called BEX whatever that means. it happens with various projects. i dont know why though since the same level was compiling fine with an earlier version of the map compiler.

Can you send that level to Support, or upload it - together with a list of your map compiler settings - so that we can look into the problem?

will do that