This works like a dream in Drawplus. The colours don't really matter so much to me as I can set those myself, but could I request:

a. Is it possible to have the numbers on a separate layer to the hexes?
b. Is it possible to have different numbering options? For example without the comma or A0, A1, A2 etc where the letters correspond to columns. (trying to think of other conventions)
c. Is is possible to have an optional dot in the middle of each hex (again on a separate layer) to measure lines of sight? (I know some games use these).

I think this is a one of a kind application on the net, you should mention it on Boardgame Geek. I'm sure there are a lot of folks over there who would appreciate it.