I recently bought 2 KM01's.
I've wired them up according the following schematic:
I set interlock 1,2 and interlock on, updated to the latest (tasmota) firmware, buttondebounce to 300 and switchmode to 1.
But no matter what I try, the KM01's won't register any input on S1 or S2.
The weird thing is, that when I set the KM01 in parallel to the switch and keep the motor connected to the switch (so both switch and motor are connected to S1 and S2), the KM01 does register switch input. But offcourse in this config the motor can't be controlled by the KM01.
One thing I noticed is that in correct configuration, S1 and S2 both measure about 115V when open ( I live in the Netherlands, with 230V AC), but with the motor in parallel, both are at 0 volt. This seems to suggest that some pull-down resistors are missing on S1 and S2.