We've been traveling with our girl, now 2 1/2, since she was born. We have an RB50. Until she got a bit more mobile we put her in a pea pod "travel sleeper."
http://www.kidco.com/products-page/peapod/
We would pull down the back half of the penthouse bed and bungie the pea pod in place up there while we slept on the goucho below. We rigged up a blanket that would drop from the ceiling down in front of the pea pod to keep it dark so that we could keep some lights on in the van.
Once she got bigger we just changed positions with her. We put her behind the the rear seat (with the goucho folded up) and we slept in the penthouse. We again rigged up a blanket to block off light from the rest of the van.
She has gotten too big for the pea pod, so we have ditched it and let her sleep behind the rear seat. We've been worried about our dog trying to snuggle with her during the night and creating chaos, but keeping the blanket blocking her space from the dog's spot on the rear seat has worked well.
I should add that the pea pod folds down onto itself and is thin enough that we can slide it in cabinet right next to the porta potty. It's worked great.