Launching a new game with M&S installed with armoured biters on results in all Nauvis Snapper Spawners reverting to vanilla biters.

I tested both the moisture check and armoured spawner options, and neither enabled Snappers on Nauvis.

Im having the same problem but I believe thats just how the mod is set up as in the Factoriopedia it shows that the Armoured Biters spawn only on the planet Circa. I really hope we can get an option in the future to change this so we can simply pick what Planets we would like them to spawn on. :D