Then I exported the model as an fbx and imported it into Unity. In Unity, I applied a material to it which has a texture assigned.
For some walls it looks fine, but for some walls, the direction of the UV map is changed for some reason, and the texture doesn't look right:
How could I set up the "direction" of the UVs in Blender and not just hope that it will work out alright (which it obviously doesn't)?
Thank you very much!