I solved my Crusader M problems by carefully removing everything that said Anilam on it and replaced it with a more modern control system that has the features that I need and is easily expandable going forward. I know this is not what you want to hear, but it is a 30 some year old controller, and not very adaptable.
I did look back through some of my archives and was not able to find a way to extend the I/O on the Crusader M. Not saying there is no way to do it, I just don't have an answer for you.