http://www.daz3d.com/forums/viewthread/32978/

akulla3D I'd be willing to bet you use DIM. Stop using it and install to an unprotected folder. W8 wont let you write to the protected content folder in the carrara folder in the windows programs folder; yes that was a lot of assuming as not alot of info was given. 

"Yes, Michael 5 works perfectly. I was able to change his skin. Moreover I was able to add props.

I was eben able to animate some blood-particles on his skin. (yay!)" patrickgobels

I have to wonder just how much work you have done with M5 in carrara; considering just how badly genesis and autofit work. A naked genesis works well too, it's when you try to put hair and clothes on him the fun starts.