correct, no official UBB classic converter - though there is one by SMF's mike bobbitt for early UBB/SMF versions. he's not interested in pursuing updating his converter, but his old converter is available. AFAIK, UBB threads isn't stand-alone. we want our own forum software, on our server. we're using SMF for other forums and like its platform.
You guys are missing his question.
R. - ubb.threads is standalone - install it on your server. Use MySQL, go crazy
You may be thinking of the spinoff social-strata (or whatever their name is now) is doing, which is a hosted forum.
I remember Mike Bobbit, long long ago
If LK couldn't import, I don't know if anyone can. That said, what is special about your .classic that keeps it from importing? I've imported larger forums than that. Are there extra profile fields? Something else?