Interesting topic, I read your post falcus.
Why make it so complicated by trying to edit this into old msts .eng.
It would be easier to implement this in newer OR only files. Sure time to do this is not yet here.
A real weather engine would be nice to go with it indeed, wind, rain, storms etc.
When OR makes a real breakthrough (beats railworks, which it already does in certain points) I'm sure payware developers will publish routes and rolling stock for it. If the loco's are made in state of the art programs like 3ds it isn't even that hard to export for multiple sims. the freeware NS 1100 loco was released for MSTS and Railworks, the base model is the same.
BR Jordi