During a test, I exported an fbx file from lightwave, saved it to the asset directory. Unity crashed and now I cannot get it to launch again. It brings up the submit bug window and hangs there forever.
How do I get Unity back?
I had a similar problem, i can’t exactly remember why, I think it was a pretty poorly formatted file, maybe many multiple objects. I was rushing, and used some old thing i had sitting around. The material wasn’t powers of 2 either. But I just removed it and Unity launched again. I’m assuming it gets hung up on import if the fbx is out of control.
Take a look in the console (Appliactions/Utilities/Console). As Unity imports stuff, it prints the filename there as the import goes on. When you find the file that made Unity crash, please send it to us, so we can see if its something we can fix.
I’ve tried now a number of exports of the model, all make Unity crash 
Thanks for the file… As for size: don’t worry about the FBX size - Unity stores it in its own format anyways…
Could you try to take it via blender? (Blender imports .obj, unity reads .blend)