I have both: the 'RX-7-DR Wingstabi (n° 5 5012) ' and the 'Wingstabi Easy control 7-Channel (n° 5 5010)', who is connected to a RX-7-DR compact (n° 5 5819). This last one is with the 'S' socket where I had to connect the MSB lead from the ESC. If I connected the MSB lead to the MSB socket from the Wingstabi Easy Control 7-channel I had no telemetry on my SX9.
If you want, I could send you a picture of both set-ups if you give me a mail adress.
Anyway, in both the setups the Smart Control 45 is showing the correct telemetry.
Thanks again and take care,