According to Cajomi owners of GeoControl 1 will have available public access of GeoControl 2 in a few days i think. This is all i know at the moment. You would have to inquire with him for further questions. At the moment i am only beta testing GeoControl 2.
GeoControl uses color gradients, many of which i contributed to the program and single colors that map over any terrain and one can apply them using all sorts of various means.