Setlle - Carlisle route crashing trainz


Learning... slowly!
I've posted about this before with no luck; one thread got hi-jacked by some joker so may I politely request on-topic responses only please!

Using Trainz Mac 2, the whole S&C pack - all routes and content - worked brilliantly until a few weeks ago. For some reason though, the full length route will no longer load - Trainz just crashes once it starts to load. The other routes, the sections of the full thing, and all the other routes I have in Trainz of all sizes work fine. I'm really not sure why this is happening but it's getting annoying.

Anyone got any ideas why this is happening or how I solve it?

Many thanks
The map is very big. It takes a lot of RAM to load into the game. In Tc3, it took me 20 minutes to finally get survayor to load the SAC route.
It is, but the ECML route will load with no problems, which is significantly bigger. When I load a route, I usually minimize trainz whilst it's loading and then go back to it after 5 minutes or so. When loading this route, Trainz just crashes.