Textures are a pain now

I don't understand why but whenever I want to change one of the textures like the normal map I click on that texture in my folder but instead of the game simplifying the address to levels/"levelname"/etc.
it sets it to something like document/beamng/levels/"levelname" which the editor dosen't like so to get the texture to work I have to go into the texture file and change the directory then restart the game and takes forever.