Hi, well I have used cork floor tiles and cut them with a knive to about 1 inch width. The hight is about 4mm, which would be about 2 foot high in prototype, which in the netherlands is very high, roadbed here looks like about 1 foot. But near towns the roadbed is flush with the street, so that street/track crossings are flat. What I do see is that sometimes they have an high subroadbed from sand (and plants, grass, etc). On top of this they have the roadbed of about 1 foot and ontop of this is the actualy track. I think I can simulate this with the cork. Also they use very large balast here, it is light grey and about if you lay down 4 stones next to each other it is about the with of a tie. HO style balast is to fine even for N scale track. I'm now laying down the track on the cork, which is quite difficult to get the tight corners I need, as the track springs back. I guess I will know in 48 hours if the track will hold as then the glue will have set.