The Mod Menu can be activated via an Perk the Hero gets at the start of a new game, or if someone uses an older version, it can be added Via the Compatability Sub-Menu of the Maintance Station.
and Please try to Recreate your case by trying to toggle the MSSwitchblock in-game and post the .log here in your next post, so I can see what actually is wrong.
It reaallly would help alot if you post the .log