Nice reskin Ben!
Um, as for the FMA stuff, I've never really had any problems.
I lower the ground where I need to, lay track, set any spline points to the required height, and then add the embankment. As I lay the embankment, I make sure that any spline points are in the same place as those on the track, and then set the height of the embankment splinee to 0.1 less than that of the track.
Never really thought it takes ages...I'm not sure if we both do it the same way though

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Another couple of screenies from the same set to keep the thread going along happily:
No trains at Shoreley following the departure of the NMT train...but there's still plenty to see...
Cheers
Chris