As far as commercial games go for the C64, I doubt you will see any, however I have been busy creating games and so have many other people, who knows where that will go one day... you do offer a free version but I paid $15 because I wanted an additional feature which was not there, no big deal, I use your program with all the software i create and glad I could support you, it would be a great feature and I don't see why it would be so difficult, it could be a completely separate "sub feature, unrelated to what you have now but uses the map in a separate map color editor (a separate window) with an export function, unaffecting other features of the rest of the program, seems easy to me... and might influence more to purchase, seems I've seen others ask for this as well... And if it were me, I would do it just for the fun of it...
There I've tried to convince you...