another basic question

Ron,

Ref:  http://wiki.prplfoundation.org/wiki/Complying_with_FCC_rules_on_Wifi

"The FCC regulates devices which produce radio waves. The software, by itself, does not produce radio wave therefore software, open source or not, is not regulated by the FCC. That said, the mechanism for controlling transmission characteristics in order to comply with regulatory requirements could be implemented in software, and in the case of Linux is implemented in software. This mechanism would be considered part of the device for regulatory purposes."

Regardless of the firmware in use, one designates the device to ether be operating under part 97 or part 15 rules, then abides by those rules.   For Part 97, your callsign is entered on the node and AREDN transmits your callsign every 5 min.      We are each responsible for knowing and staying within the rules under the licensing we are operating under.   I do not know all of the part 15 rules, but you would remove the callsign and:

1) (as you've already identified) Don't use a Rocket M5 with a 34dBi RocketDish at the highest xmit power.  This has an ERP 27dBm (xmit) + 34dBi (antenna gain) = 61dBm ERP = 1258.9254118 Watts of microwave energy.  (Don't stand in front of it :). )   I believe that exceeds the power emissions allowed in part 15.
2) Don't use the designated channels with Doppler Radar in the area.  part 15 firmware will use Dynamic Frequency Selection (DFS) and jump to other channels automatically.  I think we disabled DFS in AREDN as I recall.
3) I've not run into other constraints, but then I've not been looking.   

For me,  I'm using AirOS for a few part 15 links, but this is on farm land with very low noise.  

Joe AE6XE