I've turned the map into a height map and (using Bryce) converted that into a terrain mesh. Here's what it looks like in Blender:
- ERC Age's Terrain Skin Show Spoiler
The path is the shallow groove, the rivers are the deep grooves, the building foundations are the raised rectangles, and the lakes are the sunken areas.
The main area is too flat; I need to add various levels that are higher towards the upper cliffs. The lower cliffs need some jagged peaks for the waves to crash against. Plus, the polygon count is prohibitively high (200K); I'll throw the Blender "poly reducer" script at it when I'm happy with the elevations.