Perhaps you have the lot elevation bug. Here's a solution thanks to Richdre at Bear Mountain Creations.
(value) Is a positive or negative number depending on whether the lot created a hole or a mountain.
After you place the lot check it before you press the accept button. If it is not level then press the cancel button and try it again. Positive numbers raise the lot and negative numbers lower the lot. You can use a decimal point to fine tune the elevation. If -2 lowers it too much try -1.5. Just keep typing the cheat before you place the lot, changing the numbers until you get it where you want it. It may take several tries but it's possible to get it level with the surrounding terrain using this cheat.
When you are done placing that lot if you plan to place more lots you need to enter the cheat and set the value back to zero.
Interesting topic that has me asking questions about a house that I've built and am hoping to upload to the exchange. I suppose this is something that the downloading player has to do on their end.
I've built a house with a garage in the basement and painstakingly spent hours creating a smoothly sloping driveway. I'm not happy with the terrain tools because they are so touchy making it very hard to create a nice even slope, in TS2 you could clink the raise/lower terrain one space at a time to get the exact effect desired.
Will this "setImportedTerrainOffset" cheat help to preserve the driveway that slopes down to the garage door?