Those are all very good questions.
1) Cheat codes, bro. I'm not playing competitively, so why care about in-game currency?
2) No, but the game forces you to leave a gap of a certain number of tiles between every town that you place (or in this case, parts of London that might as well be their own town). I'm going to expand the towns, which will fill in the gaps, later.
3) Yes, I plan to include all of the following transportation systems:
High Speed 1 (as far as Folkestone)
High Speed 2 (maybe)
Docklands Light Railway
Tyne & Wear Metro
Nottingham Express Transit
SEWM (if it gets built)
Greater Bristol Metro (if it gets built)
National Express Coaches
Local buses in various areas