There was a work around in the old forums for the administer rights issue using terminal. You can find it in the old forum here:
“Simply open a terminal, sudo to root
(to do this open a terminal, and type sudo su - it will ask you for YOUR password)
cd “/Applications/DAZ 3D/Carrara8/Carrara.app/Contents/MacOS”
(or where ever you installed it, i changed my directory to remove the 64-bit part)
And enter your information, this will need to be done for the render node as well.”
As far as running 64 bit 8.1 on Lion or Mountain Lion… A few people have reported that they can run it. I have never been able to get 8.1 to run without crashing every time I open or save a file. I use 8.5 exclusively on Mountain Lion.