One of the things which will be worked on with Threads7 (currently in Private Beta, soon to be Public Beta) will be importers from various other products; currently I don't believe that there is a way to import from vB3.5.

There is a yaml file for vB3.0 (http://www.groupee.com/yaml/) for the ubb importers in both .threads6 and .classic6.

I am a Web Development Contractor, I do not work for UBBCentral. I have provided free User to User Support since the beginning of these support forums.
Do you need Forum Install or Upgrade Services?
Forums: A Gardeners Forum, Scouters World
UBB.threads: UBBWiki, UBB Styles, UBB.Sitemaps
Longtime Supporter & Resident Post-A-Holic
VNC Web Services: Code Modifications, Upgrades, Styling, Coding Services, Disaster Recovery, and more!