I've been busy. I've spent the last few evenings assembling the electronics that will enable me to control all the pneumatics from a PC. I've made two mistakes on the board design:
1) The linear regulator holes were too small. It was a simple job to drill them out to the right size but this removes the through hole plating, the result of which is that I've had to solder the pins top and bottom.
2) I got the pad spacing of the 25 way D type connector I was going to connect to the PC with completely wrong. So wrong that the conenctor I wanted to use will not fit in the holes. Fortuanately I had some 25 way cable lying around (as one does) and I've soldered this cable directly to the board and put a connector on the other end to plug into the pc.
Here's a pic: