@Zwer2k my expectations seem correct. I created a bug report that also includes a rudimentary workaround.
https://github.com/mysensors/MySensors/issues/1496#issue-968399284
I've added all the files manually so things should be there now (though I'd recommend grabbing things from github to preserve directory structure and get all the files).
I have published all the documentation in a Github repository. If someone wants to make PCBs, I recommend that you wait a little longer until you receive my PCBs and try them.
https://github.com/giltesa/SmartHome
@lrtsenar
The MySensors Libraries were designed around the nrf24l01 transceivers which have much more built in capability than a simple 433Mhz Tx/Rx pair. You can make a node which contains a nrf and 433 Rx/Tx and it can transfer messages between the MySensors architecture and common 433Mhz devices. If you are only interested in 433Mhz devices with Domoticz, see the RFLink project for more info. I believe it requires a mega to fit their libraries.