It will detect (probably) rain and update the sensor value, but it will for now not update the sensor value if the window is not moving.
Because of the weird way the KLF closes connections, there are two extra flow cards that will allow you to restart the KLF. (i.e by added a Zigbee Switch to the power supply)
I do not have anything else than Window Openings, so if anyone are able to test with Blinds then it should be possible to add more features to them in the future.
It works with the latest version of the firmware, and it only works after a restart of the Velux controller (as there is a timeframe where the controller allows connections). You should have a fixed IP and set it up with the fixed IP, it will not discover on its own