same problem.. I have vista 64 ultimate and when I try to create a scene this comes up:

Well I found one solution which is to download the free Microsoft Virtual PC x64, put it on the vista 64, and install vista 32 in a virtual machine. It's a pain but once it's setup it does work.
hmm.. this might work.. I have xp 32bit in vmware .. imma try this..
EDIT:
..nope.. does not.. first of all cause I tried it in xp32 bit.. duh
but I will not try vista32 bit just for this ... PLEASE FIX THE PROGRAM TO WORK FOR 64bit Vista!