How can I build no-slope basement on a one click high foundation using Grid Adjuster. I just downloaded some Simpsons furniture of The Sims Resource (it's free if any one is curious) and I want to build The Simpsons House including the basement. How can I build no-slope basement on a one click high foundation using Grid Adjuster, I once build a completely sunken basement using slope cover fences and objects but the only way a sim could access the house was by entering through the basement's external access (the front door was useless), I want to be able to build a no-slope basement on a one click high foundation using the Grid Adjuster. Can someone please give me clear instructions on how to do this or something similar.

Which part are you having problems with?

If your only problem is how to convince your sims to go from the ground to the first level, here's the thread that you're looking for:
http://www.modthesims.info/showthread.php?t=402863

Thank you for linking me to that thread, it could really help me on future projects, however, it won't help me on this one as an attached garage is not possible using these techniques, I ended up settling for a basement with sloping ground under a one click high foundation.