Yeah that's been bugging me too. Was going to go reinstall, but it might just be broken
Yeah, several of the mayhem/safeguard maps are buggy.
This was just brought up over at the VidiotMaps forums. Turns out the problem is with the actual in-game maps. It seems they've changed, so the overlays no longer match up.
Blondeshell will have a fix as time permits. 
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Biggest Troll on the forums? I'll give you a hint:
It's not even that the standard in-game map images have changed, but rather that the mini-map mechanism appears to be busted for Safeguards and Mayhems. If you uninstall the VidiotMap overlays, you'll still get the same bizarre performance. For example, your position will change sporatically as you move around the map, or even as you adjust the zoom slider. Until the bug gets fixed, the best suggestion I have is to print out the VidiotMaps as a reference, or alt-tab between the site and the game.
Blondeshell (1381 badges) - My other badge hunters
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Is it me, or is something buggy with the safeguard mission maps. The badge I'm looking for in the safeguard is ALWAYS outside of the area I can access. I have the latest download.
Call me,,, Mal