Since nobody's said this yet, I guess I'll be the first: You're much better off putting the entire scene together in Carrara alone; cutting Poser out of the process completely :)
Technically Carrara hasn't supported the import of Poser scenes since either Poser 5 or 6; I first noticed issues whenever Poser Pro first came out. Poser content however is fully supported; just point Carrara to your Runtimes and you're good to go.
Another issue may be that Carrara isn't finding all of your Runtime paths; a common issue if you're using an external drive.
Also, after your Poser scene imports, you may need to re-conform clothes, hair, etc. Sometimes advancing Carrara's timeline to frame 2 fixes the issue as well.
Either way, you should at least try putting a simple scene together entirely in Carrara and see how it feels :)