Hi Guppy,
Welcome to the users group. When I follow the image link I get:
GameDev.org wrote:It seems that you are not allowed to download or view attachments on this board. Please login below or register an account with Gamedev.org.
Any chance you could upload the image to
the users' gallery on this site?
As for placing vegetation; this is something that's on the to-do list for next year. You can however generate a mask map using the alpha map generation feature, by combining all the grass layers into one layer, then saving the alphas as 1 layer/image. This will give you a black and white bmp/jpg/png showing areas of grass, which you can use to place vegetation on your map.
Cheers,
Aaron