I have two Retrofit Alarm Kits, one for the casement windows in the kitchen and another for the casement windows at the front of the house. Each RAK is bypassable as a single unit, not by each zone inside the RAK, so for my needs I have two of them. The setup was easy. I have an issue with the second RAK which I think is defective, but the first works like a champ.
Update 1-15-2020: I called Ring’s help line (800-656-1918) and the tech reset my second RAK remotely which then lead to 100% success. I was unexpectedly surprised and impressed. Sincere thanks goes out to the Ring Alarm team.