Hi Rob,
OFX and CSV are both static formats, I think. It's just that the old Numbers I suspect was smart about how it interpreted the OFX format. You could replace that built-in functionality by rigging something where you dump your imported CSV data into a "source" table and pull it out of there into another table with your customized column arrangement
Agreed on those sheets on the left side, though. Very convenient. They got the old heave-ho, I suspect, because similar implementation on a touch interface just wasn't going to work. Also, I saw a comment by Jerry that a lot of users, oddly enough, used to complain about them being on the side instead of on the top or bottom.
I think I read somewhere in the discussions, I think at the bottom of this thread, that there is an "updater" that can be downloaded. I'm not sure it applies to the version you have, though. Anyway, you might want to pursue that angle, as I would guess Apple doesn't want you stranded in the past.
SG