Well, when diving into the Pratchett worlds, get yourself a copy of Mrs. Bradshaws Handbook for travelling upon the Ankh-Morpork & Sto Plains Hygenic Railway.
Meanwhile the KEG is trying to teach young swamp dragons how to fly with the help of a starter wagon.
You might have guessed it. The locomotive is one of the first Gn15 laserkits, cut in 2008 by Harald Brosch after an Oliver Zoffi design and assembled / modified by Ralph B. in Norwich. Meanwhile part of the KEG loco fleet.
The figures are modified LGB / Elita models, which you can get unpainted from http://elita.de/