Well, before I exited the game without saving, I did save a copy of the lot I had built. However, when I restarted the game and tried to import that lot, I ran into the "processing" icon into infinity again, so I had to force close the game with the Windows task manager. SO annoying.
I ended up reverting back to the original game, which I had thankfully backed up, from this morning. Fortunately I remembered what minor landscaping and building changes I had done to the house and just ended up re-doing all of the steps, going back to the town and saving after each section. It seems to work for now. We'll see what happens if my Sim couple actually saves enough money to move into the lot... I seem to have trouble with the 60 x 60 lot in general, though my computer is way overpowered for the Sims 3 and I have 4 GB RAM.
