Waldronate is the guild master of FT Pro and Wilbur. In the mean time, have you looked at Wilbur as well ? I was led to believe that it had some height manipulation ability too and I think its data is compatible with FT Pro.

Wilbur:
http://www.ridgecrest.ca.us/~jslayton/software.html

Ravells has just posted about another height map editing program which might create data compatible with FT Pro:
http://www.cartographersguild.com/sh...diting-program