Cannot place objects in a split level apartment

[sims2fan473]

It seems split-level hates me right now! :faceslap:
I made split level apartments but i've moved a family in and now realised that the path to the toilet is blocked by the sink. I then tried to move things around and i have discovered i can only place objects or delete objects on the new foundation level. I cannot touch the lower-leveled kitchen or the upstairs floor. (The apartments are designed as small rental houses) Does anyone know a way to overcome this? I would be really gratefull if you do :help:
Thankyou!

[Mootilda]

You have an invalid apartment. It's quite possible that you can't do what you want (split level apartment):
http://simswiki.info/wiki.php?title=Tutorials:Building_an_Apartment#Split_Stairs

[sims2fan473]

Oh dear :( How annoying! I've placed about 20 of these in my neighborhood...now to go change them all...thanks for your help!! :)

[Mootilda]

You might want to wait to see whether anyone has any other ideas.

Also, the FAQ seems to say that they'll sort-of work, as long as you don't have to make any changes once the apartment has been zoned.