File names are :-

<Manufacturer><Gauge><Stations><Traction>[<Slip>][<optimised>].scarm

<Manufacturer>
	P = Peco
	Ar = Arnold

<Gauge>
	N
	OO (maybe one day!)

<Stations>
	<Position>To<Position>
		In = Inside the circuit
		Out = Outside the circuit
		EE = End to End

<Traction>
	MU = Multiple Unit
	Loco = Locomotive (obviously MU can also use the layout)

[] = if present

<Slip>
	X = a double slip is used
