Well, I did sucessfully manage to couple last night without crashing, but I still had a couple of problems. Firstly, the saved activity (I had to resume from a save at the point when notified as MSTS crashed on coupling on the previous attempt) doesn't want to load the AI versions of the .eng files for some reason

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Secondly, I got stuck at the signal just after Bamber on the way out to Steyning. I suspect I probably arrived a little early, but only by a few minutes, but the signal stuck on red until well after I was due to leave Steyning on the return to Brighton.
Well, nobody else seems to be having the problems, so I'll give it another whirl tonight and see how I get on.
It is an excellent activity by the way, with very nice use of low poly static consists.
Paul