Regarding point 2 above, remove the solder jumper at the output of the mkr wan power supply when using an external power supply. This eliminates leakage from the external power supply into the mkr wan's power supply.
Regarding point 2 above, remove the solder jumper at the output of the mkr wan power supply when using an external power supply. This eliminates leakage from the external power supply into the mkr wan's power supply.