Hi Jaba, I have watched the full replay and it seems the system worked as designed. But
At no stage prior to you passing behind the other aircraft were you ever above him, therefore you were climbing through his level whether he was on climb or not.
Assuming the reason you wanted to gain height quickly was because of the rising terrain on your outbound track, and as you know, the responsibility of terrain clearance until reaching LSALT/MEA/MORA for an IFR flight, remains with the PIC, with see and avoid still being applicable to an IFR flight when not in cloud.
I can't see the other aircraft did anything incorrectly assuming he was 'clear of cloud'
As you alluded to, I think it would be a good idea to send a carton of 'coldies' to BNE ATC with a thank-you note attached.
(Thankfully you weren't on approach to Pa Kettle's paddock on a frequency different from 'Area').
I'd miss you around here.
regards.