Dear Andy,
Your wiring seems to be completed as Spirit requires. I wonder why you wont get the results.
I had connected the Yellow RPM wire into FC (Spirit Pro) and I am getting solid RPM reading. I am using Futaba radio and RX and I had to use another Spirit made cable to connect the FC and RX via S-Bus2. You may connect the yellow wire and see the results. It wont make any harm. If HX and Align share same features, you must get RPM reading from that.
By the way, could you describe the connection wire sequence of UNI cable, on both ends. I am thinking to make a temporary cable and try. I had seen on several places Mr.Tomas commented that just removing the RED wire between ESC programming and SAT1 cable shall do the job. I just want to be sure. Mr.Tomas didn't answer my question regarding the self-made UNI cable yet.
If I order the cable from Spirit now, it will take minimum 2 weeks to reach to my end.
Mr.Tnjet, I have Align RCE-BL80A ESC on Trex 500XT frame with Futaba TX and RX with Spirit Pro FC.
Regards,
Amal