Glad to help. The forest colors are all one forest type. They're just different elevations as well.
If you want noticeable hills, you'd want to paint two grass (or forest, or sand, etc.) colors with at least 10z difference in height. Or, if you wanted your forest to be a bit higher than your grass, you'd paint something like 0 grass then 5 forest - or however much difference you want the two heights to be.
However, if you want those "cliff" things, like in t2a or around the Trinsic Moongate, you'll need to use the "grassbump" colors. Unfortunately, I've never done that so I'm not positive how that works. There are tutorials on this forum that can help there, though, if you do a search for them. Just look for "grassbump".
As for transitions: You don't have to actually paint a color for transitions. Dragon automatically places transition tiles between two different types of terrain. Please note that transition tiles where THREE types of terrain meet do not yet exist (I believe it was mentioned someone was working on those but it's a VERY large project so I don't think it was ever finished) so you'll have to use another program - most use Worldforge - to tweak those areas to make them look nice.
-CMS
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