Hi Kier, thanks for the response. That does sound like the smart move. Problem is that I don't have access to the database: perhaps a bit of background would help.
We've been working at a forum for the past few years, accumulating a fair number of posts. We'd like a backup of these posts in case anything happens to the current forum, as a archive/reference in the first instance and perhaps as an active forum if things go wrong.
The forum admins at the vB4 forum are amenable to this, but for obvious reasons would not want to give us a backup of the entire database or do any substantial amount of work on our behalf.
I guess what I'm asking is for the minimum required for the current admins to include in the database dump in order for XenForo to be able to create a working database, eg if they dumped and then pruned the forum tables to just our 6 forums, would I be able (with a bit of hard work and ingenuity) to fashion something that your import script would accept?