I ran a couple of images recently with layered volumetric clouds in Bryce 6.1. It took me about 4 hours for a 2400x1230 output on my quad. Didn't notice any pause at AA stage. 

Sackrat, don't toss your Bryce when you dig into C4D. It still makes a great support tool for C4D projects - I'm still using it!

Pass no temptation lightly by, for one never knows when it may pass again!