I see a lot of people having problems with Train Simulator! I had myself lot of problems before. But then I decided not to use any workshop routes. And after that I have not had any problems with Train Simulator!
Workshop items can cause problems if they don't install properly but I reckon it is one of Train Simulator's greatest assets. You will avoid some issues by avoiding the Workshop but you'll also be cutting off your nose to spite your face.
There are problems, I have reported this here in this forum. It's really aggravating. Subscribing To Workshop -> Temp Dump 0xc0000005 Access Violation With care and attention it works, but the process of creating the scenario from the Steam global cache has problems that can result in corrupted scenario. The above post is very detailed.
