Nevermind I had a reply somewhere else. This is how you do it.
use this link to go there -
http://tinyurl.com/2498bpBasically, you can't open SimPE normally. You have to go to File/Open/My Documents/Castaway Story/Neighborhood/Noo1/Neighborhood Package.
By opening the neighborhood package, you'll bring up the story neighborhood, that's N001 but you can do the same for the Noo2 hood also. Then in the left panel you'll see Lot Description. Click on the lots you want to change and you'll see a pull down button, it will say Community if it's community lot. Change that to Residential, click Commit then Save. When you place a sim on the lot, the build and buy buttons might be greyed out. Just make sure to save, exit the lot, then reenter. If they're still greyed out, do this until they aren't.