I checked the link, nice setup man, looks smooth
If its complaining about the primary ignition signal, Id assume that to mean the CAS isn't behaving correctly. I'm not too familiar with RB26 CAS's, but id assume its a photodiode and chopper disk setup. 360 (=20) home slots and 6 trigger slots. If "Primary Ignition Signal" isnt refering to the whole CAS, maybe just one of those ouputs is broken, as i didnt think a RB would even fire without a CAS. I guess the obvious question is, have you tried a different CAS?
I'm just just thinking aloud here
GoodLuck