Baz66,
Good news, glad you got it going!
Head for the Downloads section, then TRS2004 or TRS2006 as appropriate, then Activities (Public). RBR subscribers have access to many more activities in the Activities (Subscriber) sections.
Avoid our RBR T4 Scenarios (Closed) section which contains old items which are likely to give you problems.
Use Janus (for TRS2004) or Argus (for TRS2006) to download missing rolling stock assets in the form of self-installing asset pack exe files from our server. There are full details of how to do this in our FAQ.
If you have any problems post here or probably better on our forum. Happy driving,
John