So I have just completed the mission where you have to dispose of the retired demon. I then had to quit from the map screen, but on reloading it found no locations on the map and I am unable to profess. I reloaded, verified the game and even deleted my progress file, started the game again and then when I got to the map screen, found the same problem again. I have already started this scenario again because of a game breaking bug, am I going to have to do it a third time? Because frankly I’m sick of being sunk in this game through no fault of my own.

Sounds similar to a problem I'm having; I have locations on the map, but no me... The cow skull that usually indicates which location I'm currently at is nowhere, and I can't travel to any new location by clicking on it.

I have no solution for you; just me-tooing. I'll let you know if I find anything.