Well, time to resign as my last little hope ...Rc8 (which would be unlikely to work anyway without time-pressure) fails miserably to Nxd4 when there is a big fork on e6.
Well-played Clement! I'm looking forward to reading all the comments from you and the others :)
What went wrong for me? Basically I played it a bit too much like a normal OTB game, and didn't check the little tactical details closely enough when I decided to abandon the q-side.