It probably has to do with either of two things.
The more likely thing is map size. A large map will crash rediculously. My reccomendation... Log in, find out where you want meshes placed(Write it down) and place the meshes one by one. Or just... shrink the size of the map. If you HAVE to have it that huge just split it up into multiple maps. A good size is 50,000 to 75,000.
The less likely but still possible thing is a corrupted mesh or object. Sometimes, meshes will not instantly crash something, particles especially(If a frame of corrupted animation is played), due to faulty coding. You may want to check over which meshes work in your Object Maker before continuing.
Otherwise, there is a last resort. I've had to do it before. Re-install FH. A backup would not work since it is likely a file is corrupt, so you would have to restart... Try making it a smaller size. You may also want to make sure your HM and TM's are all 513x513, but that is usually instantaneous with crashing. Save FH when you place a mesh if you don't want to do this, it will prevent you from losing a lot of work. Hopethishelps.
