Thanks for all your help. I finally have it working now. To be honest I am not sure exactly what the problem was. My firmware is v26 which I just updated recently. I went back and checked that IN1 would still trip R1. Then I went back and checked all the settings for Analog 1 again.
This morning the Group number for Analog 1 was set to 2 instead of 3 and I am pretty sure I saw it set to 3 last night. I also checked each of the other Link Command settings and performed a WRITE. I frequently get timeout messages, so I confirm any changes I make by doing a READ after any WRITE command I make. If I get any timeout errors, I repeat the READ.
I don’t see how a wrong group number could explain why I was not seeing any insteon activity in the DM, but obviously one of my settings was incorrect. Perhaps writing values for Input1, Input2, Analog1/Alarm, and also Analog2/Alarm solved the problem.