Thanks everyone for the interesting and varied solutions.
I was not expecting the amazing trebuchet launchers, and even Paolo's gibbing crane catcher is a masterpiece in it's own way.
There can be only one winner though:
1st Votart Silak 1692 Congratulations!
2nd KuzyaHG 1654
3rd Alex 1602
4th Paolof 1470
Kuzya's launcher and Votart's catcher represent "best in class" - I've combined them for a score of 1712 (included in .zip).
Over and out