The board you are using is just a pilot pneumatic valve unit. It simply turns the valve on and off, the output pressure of that valve, and all the others on that manifold, will simply be the common input pressure. You have have done well to set the valves up on the Ips, it's like a secret language ABB don't want you to know!!!!
The brush tables will set the Atomizing air, the fan shape air and the paint flow via the fluid regulator. All set up in the Ips. But.... you need a PPRU, a proportional pressure regulator (I think). This basically converts a digital electrical signal into an air pressure, using 3 output channels, very accurate and constantly monitoring the pressure in a closed loop. Very expensive as well. It is set up in the ips, and simply put, outputs the air pressures in the the 3 channels at the correct pressure to the brush table.
Have you got one of those?
Are you using irc5P?
I bought a irb5500 on irc5P, second hand from a BMW plant and lost a year of my life learning how to use it!!!!! There are good manuals for arm, for Irc5P but nothing really for setting up the ips. I took the BMW set up already in the robot and stripped out what I didn't need, added what I did.... but it was a long slow learning curve!