Thanks Fran,
yes import the BVH file into DazStudio after having selected your Daz model apply a background colour say blue if you wish to chroma key the model into a video editing program (i use Ulead Video Studio 10+) this seems to work well.
Carrara will import BVH and FBX have since found out but Bryce will not.
Some BVH files when imported into Daz get distorted,and finish up like matchstick men oops persons. have yet to find out if i can fix this or not, however i downloaded BV Hacker from Dave dub which allows you to adjust settings within a BVH but havent got that far just yet. There dose'nt seem a lot of interest out there in this type of file. but have learnt a lot through asking on Google.
Thanks for your interest Fran.