moving from one blackberry to a new one, BES account activated on new one which seems to have transferred the bbm contacts
I transferred SMS history via DM selective restore

Is there any way to transfer the BBM conversation history? I found some internet stuff referring to csv files that you could alter to work but I haven't had any luck with this. Is this do-able?

old device was 9780, new is 9900

With limits, no attachments yes using Blackberry Protect. Install it on the old BB and restore on the new BB.

KB25062-How to use BlackBerry Protect to back up data on a BlackBerry smartphone