Problem with terrain imports

Hi, I downloaded some actual USGS terrain data and turned it into a 256x256 grayscale and imported it into TGE. For the most part this worked great and after applying some of the default "patchy" textures, I ended up with some really cool terrain of about a 1 mile^2 of the Bridger mountain range in Bozeman, MT. Anyway, it has two problems; one is that in the terrain it has a few steep drops or cliffs that show up, most of them seem to be what would be at the edge of the terrain (where it starts repeating), but a couple are in the middle of the terrain. I'm assuming that this results from some problem with the bitmap, and because of the extreme terrain I end up with sharp transitions at the edges, where the terrain repeats. The second problem is that I can't fix it with the terrain editor; regardless of the brush size, all I can do to smooth this out is sort of "peel off" a little bit of the "cliff", after that that portion isn't selectable/modifiable anymore. So, does anyone have any tips on how to either avoid this problem (is there anything I could do to the bitmap to avoid this, turn off the repeating of the terrain, etc.), or, is there anything I can do in the terrain editor to manually fix/smooth these problem spots. I'd really appreciate any advice; this is so close to having some really cool terrain...

Thanks, Marcus