Thanks for the kind comments. And thanks to those who answered people's questions for me...I can't always remember where I found GRFs so that was very helpful!
Sadly, this game might be coming to an end. I've bitten off more than my laptop can chew. I had chosen a stupidly large map (4096x2048...I know, not recomended...but neither is drinking beer and I like doing that too!) so I could have a lot of space to build. I had just added my first mail route, (via 2 trucks and long distance train) when the game suddenly slowed dramtically. My computer is obviously crying enough. I knew this would happen eventually playing on a map so big. The computer had done well to get this far. It's still getting the odd burst where it plays normally but it's obviously close to becoming unplayable. I might try to set up one more route and see if thats possible!
Here are a couple of parting shots from this game. Roche and Pevensey (2nd largest city over 2000 tiles away) both had frieght terminals built. these were designed to handle a lot of mail and goods. Well I managed to set up one mail route and that was enough for my computer.
Trucks take mail between the city centres and the terminals. A train then carries the mail between the two terminals. Was hoping the train was going to be in one of the terminals so I could have it in my pictures...it's out there somewhere in between taking an absolute age to get anywhere thanks to my laptop!

- Roche Railfreight Terminal.png (137.96 KiB) Viewed 360 times
Then the plan was to have a flurry of trucks and trains in these freight teminus' (or is it termini?) transfering goods and mail from all 4 corners of the map.
Ho hum...back to a more traditional game then!
Edit: Found my mail train!

- There it is!.png (113.42 KiB) Viewed 360 times