[agracier]

You might also consider using psd files to work in. That way you can make as many layers as you want, delete them, superimpose them, merge, or change order in the layers .... this is very useful when tracing roads or rivers or using Google earth map info on maps you are working on.

And Paint Shop Pro, even the old PSP 7 version, is far more versatile and easy to use than GIMP.

When you have a psd file that is finished, then in GIMP you can easily convert to the right type of .tga.

For some reason Paint Shop Pro (PSD7) does not convert tga to the correct type for maps.