Regarding bus routes
Do a search on my username and in January, 2011, you will find a posting I made with some (hopefully) helpful hints on bus routes. After that post, I installed TS2010 and can't get Swiss Post Bus to work in TS2010 but did work for me in TC1&2. Fortunately, I found a substitute.
Since you are British, and assuming your route is set in the UK, you don't want Swiss Post Bus. There are plenty of driveable buses on the DLS from England, Scotland, Australia, Japan to try out (doors on the left side).