Not a game breaking bug for me but a bizarre one as it only happens in this location but whenever I try to pass an AI AP Class 156 between Marsden and Slaithwaite the game crashes with the following message below. I've tried putting other trains in the 156's place and it works fine and the 156 doesn't crash the game elsewhere but if anyone can let me know why it's happening only in that exact location then feel free to let me know.
There's a mention of several AP packs being updated "Fix for crash if AI passes signal HU721R on Huddersfield Line within ~4 miles of player train" in the latest AP Update log - AP_Update_Log.pdf. The 156 isn't one of them but it's been updated since so may well have also had that issue fixed. Worth getting the latest version to see. I always keep the previous versions of all my AP packs in case I need to revert to the older ones.
Ahh okay I see. To get the latest version do I just reinstall it? It's just really odd because it's only in that area like I have a 156 running out of Manchester Victoria and it's fine it's just that one between Slaithwaite and Marsden
Just get the current version of the156 pack from your account on the AP site and install it. Doing so will overwrite the one you've got installed and bring you up to date.