Raised roadbeds in the yard

[doctorwayne]

I have each line in my yard on subroadbed, should I pull these out, and either lower the tracks to the foam, buy a sheet of cork, or leave it as-is??

You could leave it as-is, or fill in the low areas with the same material that you used for sub-roadbed. Use joint compound or patching plaster to fill any gaps, and your ballast will cover-up the patch job. Don't use joint compound to fill the low areas, though - applied too thickly it will crack severely as it dries.

Wayne