Carrara 3 wont work with any DAZ/Poser content. That build was long before poser content could be used. Carrara 3 is years out of date.

No C8 wont send scenes to Studio; why on earth would you want it to? Studio is inferior for rendering.

Bryce can send scenes to Studio? I know Studio can send scenes to Bryce, didn't think it worked the other way. Same with Poser and Vue.

But why on earth would you want to send scenes from Vue, Bryce, or Carrara to Studio or Poser? Carrara, Bryce, and Vue have much better render engines then Studio or Poser.

The way it works is you stage the scene in Studio, then send to Bryce to finish and render. Same with Poser and Vue. Carrara has no need to send anything anywhere. It's quite capable of doing it all on it's own; excluding Genesis and G2F/M.

Which is the best for scenes depends on what you want to render. Both Bryce and Vue have better atmospherics then Carrara so would do huge out door scenes more realistically. Carrara renders pretty much everything better then Studio or Poser.

For me Studio is just a suport app for carrara. Sending scenes to Studio from carrara would be several steps backward.