@anvil - great code sleuthing! I have been absent due to travel but to ensure this doesn't slip through the cracks and create future confusion for other users, I have filed GitHub issue https://github.com/mysensors/MySensors/issues/770 to add these defaults into the RPI gateway example for the 2.2.0 release. With your increased familiarity with the code base, feel free to make the change and submit a GitHub PR if you are so inclined, otherwise it will wait until one of the core members makes the change.

@Tmaster I'm actually using a LG Exceed 2 that comes on sale for $8 at Best Buy every once in a while.

@gregl said: I think the main reason why most door/window switches are usually NC is so that should a burglar gain access to the wires to the sensor and cup/snip them the alarm would be tripped. Of course in this type of use batteries are not a consideration.... Back to mysensors.... i too like the status sent periodically so i know if a sensor is alive or dead. Fair point. When it really comes down to it, I got started thinking about this in relation to a mailbox sensor. I want to put it there and not touch it for a year. It's flippin cold in Tennessee right now.

No, youre right, that wouldnt work for battery powered. I chop the ends off old cell phone chargers and try to keep a room's sensors down to a single box. The only one I've considered being battery powered is the "Mailbox opened" one but thats another project. The polling is really just to allow getting realtime data when you want it. If I think about it more, Ill probably leave it out. I was just thinking out loud near the end.