Yes, Indigo seems to be working correctly. The problem seems to be the threshold of the ZSMOKEs. It is askimg for new batteries when they are in the high 70s. I tested the batteries after removing them from the device. I don't have a very detailed tester but they are both well into the green "good" zone.
I guess one option is change them when they are at 80 but that would be very often. We'll see if using the lithium batteries makes a difference.