Sadly Robbo even the updated 180 did not stop the AI colision. Not to worry though because that is the thing about creating scenarios….in life there are always what if’s, so when we create a scenario that has problems, you have choices, give up or create a scenario around the problem to solve it, just as would happen in real life. I have completed stage one of the scenario so i will begin work on stage two tomorrow. It should not take half as long becuase there will be fewer AI. I would love someone to help me resolve the issue over editing the route. I have planty of time on my hands to do just that. For some reason I am unable to save any modifications I make to the route, every time the computer goes into a screen freeze crash and a reboot is needed. Of course when I o a reboot I also have to reinstall the route too , his is because the track files go missing. There are a few signalling issues at Peterborough, Doncaster and Retford that I know about, there is of course the missing catenery on the Edinburgh to Newcastle section and for some reason there are a few catenary anomallies ( anomalies by way of unsuported catenary arms. I love this merge despite these little foibles and despite the ever present out of memeory crashes that seem to make TS 2021 such an unstable platform to work on.