Thanks all!

@Eilathen, not much chance of a tut, since it's made in Serif Drawplus and I think there are only 3 people on the guild who use it!
@Tilt, it's made in Serif Drawplus which is a vector app with some raster functionality.

Seems a shame to do a test piece like this for a map which is never destined to be used for gaming. I've found someone in the maps requested forum who is looking for a map for his/her gaming group, hopefully it'll get taken up and then the map will actually have a purpose.