It can be really annoying when there is a bug that you just can't reproduce, hopefully GraPhiX will be able to provide the information you need to find it. I haven't had the issue myself, but from what i've seen of what people are saying about it, it looks like it may be something to do with multiple EBE projects overlapping in the editor, that seems to be the most common factor that i can see so far.
As to the new terrain system, i am eagerly awaiting this, it's one of the areas of the editor that really needs improving.
One of my biggest issues with the current terrain system is they way it blends the layers, quite a few terrain sets i have are ruined by this layering system because you don't always want to paint them in the order that it's set up in, so you end up with a line, or ring of a third texture sitting between the two textures you are using, which looks really bad. If while you design this new system you could lose that layering issue and make each texture actually blend with the one next to it, that would be awesome.
Another of my biggest issues with painting terrain is the grass, at the moment it seems to be acting as a 5th terrain texture rather than placing grass, what i mean is when you paint grass it returns the terrain texture below it to the default texture, i know i mentioned getting rid of the layering system for terrain textures, but would it be possible to add a layering system to grass painting so that it sits on top of terrain textures instead of removing them?
Something else that is really needed for terrain painting, but is probably beyond the scope of what you are prepared to do at this time, is the brushes, what we really need is a way to change the shape of the brush, a couple of basic brush shapes; lines, squares, and so on would be awesome, especially if we could also ge some hard edge brushes so we can paint straight lines in the terrain (would also be good if we got those brushes, if they could be used for terrain sculpting too).
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