@therik No, I haven't solved it. But I haven't tried much either. The IKEA Molgan piggy-back-pcb is a openhardware device used by many people. One would think it either works as designed or does not work. If the radio is broken, that is one thing, but I have tried two radios. And the sensor can send data, the gateway responds, but the sensor does not recieve.
I have also tried to changed the radio to a RFM69H... that works. I get no errors. The RFM69H is a Rasperry Pi gateway, the NRF24 is the Sensbender Gateway designed my the MySensors people.
I will try on the NRF24 to add a capacitor, but again, if it is not there on original design and original design works for others, why would I need one?