My computer's being a derp about bandwidth and I can't see said youtube link, but here's what I suggest-
Build the road out of modular plates secured at the bottom by something like a 1x2 or similar, with edges hanging free from anything else. Decide on a decent size (say, 8x8 or 16x16) for the road plates, and have a handful of pre-built craters and stuff because you do not want to be fucking around with tiles that you can't get a grip on without using your nails. When cool shit happens, pick up the road section, clip out the part that is to be changed, clip in the new parts- done!
It's how most of the major military MOC guys do it, although they don't really switch plates often.
stubby wrote:omg noob, balrogs are maiars too, don't you know anything