After the update today (7/3/23) the class 37 is now undriveable in the Sleepy Delivery scenario! You climb into the cab (after hearing the ding of it selecting vac brakes and are told to stop at location. Turn the Master key, put the reverser into forward, release the train brake and.....nothing! Loco is traction locked and with all brakes released the BC value actually rises! Can't believe they released yet another fix without putting it fully through QA!
So it seems that somewhere along the line with the update when you reach the climb into cab marker the brake selection action shuts the engine down because it's running when you start the scenario. So they seem to have fixed the issue and broken something else!