Attached Link: http://www.daz3d.com/support/downloads.php?product=bryce

you can open bryce 5.5 files in bryce 5. the update patch you are looking for can be found at Daz, use the link i posted and go down near the bottom of the page, its says box version but i believe that works on the download version as well.

I have opinions of my own -- strong opinions -- but I don't always agree with them.