Odd size and rotation on .fbx import

I want to make a game with unity and downloaded the following free asset for testing purpose:
https://www.assetstore.unity3d.com/en/#!/content/91497When I import any animation of it (containing armature+mesh) or the mesh(which also contains the armature, but no animation), then the armature is extremely large. If I scale it down by a factor of 100, then the size is alright. Does this have todo with the unit system I am using?
The main problem: The mesh looks extremely weird. In edit mode it looks fine ( the character lying next to his weapon ).
I attach a screenshot, however the best thing would be if someone could download the asset and see for themselves.
The thing I circled red is the mesh. The very small left thing is the weapon of the character.
I am pretty much a blender beginner. Modeling things myself works ok now. I am currently learning about animation and wanted to check out animations of free assets and maybe try to use those rigs/animation for my own characters ( if that works after settings things up a bit … ).
Thanks for your time.