Hi Stephen
Indeed – I’d already done all that, and made no progress – not a single response on WordPress.org after a week! 🙂
I’ve also posted on BuddyPress, and have received 1 helpful suggestion that I’m about to try this morning.
BackupBuddy thought their next release may solve the missing sub-pages, and supplied me with the pre-release Dev version – sadly, the problem persists.
Cheers
Ben