Just has this happened on two PC's now.
Using the RRConfig supplied with the latest RR (October version) on an old rr.ini.
The skins paths have all their '\' taken away, so when you save and exit and then run rr, it says crogram filesriderunnerskinsidriveT is not an valid skin.
This is non-profile mode
and it happens with both the day and night skins paths
It's an easy fix as you just run rrconfig and browse each one to the correct skin path.