I have installed 3.7 and 3.66... I'm still using 3.66 cause I don't like the new camera in 3.7... but (I have no idea how this happened) 3.66 loads the custom folder from 3.7... I think other folders like replay, screenshot, etc are also somehow messed up...
I think it's a fault which happend while the installation was running
not very bad... but its strange ^^