Messed up file exported from blender to unity.

That's very strange... I can't exactly see your topology, to find out what could be wrong with it though. Look for invisible faces and go back into blender and flip them I believe there is an option in the tools panel (If you don't see it press T on the keyboard) also, make sure you have the right materials assigned. It looks like you have a black material on it. If that still doesn't work try and recalculating the normals (also in tools menu). Then removing doubles W -> remove doubles. (If that doesn't work try Shift + W) Look in the importer and set the normals to Calculate, that also seems to help, and if that still doesn't work then try remodeling it.