@EBoon, sorry I missed seeing your post this morning. Can we try swapping the Red in R1 with the Black in the Common terminal?
R1: Black and White
C : Red
Are you referring to the three indicator lights on the Iro's front cover? If so, then no (but I like the idea). You should see an event register in your activity feed however. The event will read Rain sensor activated. ([Day of week], [Month/Day], [Time])
Good catch @franz. Just need to power cycle the Iro by unplugging and plugging it back in once the rain sensor toggle has been activated in your advanced settings. For anyone else having this issue, please refer to this support article.
Let us know if that wiring swap does the trick. Fingers crossed!