I have a Macbook Pro, a Polar S625x, with the Keyspan device and the Prolific driver installed, and the black serial polar IR device. When I go into the connection window, my HRM screen flickers and says "Infrared COM 100%" (with the 1 and the black bars on the right right flickering), then iSmartTrain says "No data received".
I'm at least getting a reaction from the HRM - so I think the driver is installed correctly, because it appears to be at least sending data to the HRM. (unless my serial IR device is broken)
Does anyone have experience with this situation?