Received this promptly from my supplier 'Digiflex' and I'm happy with the service I got from them.
I glanced at the manufacturer's instructions briefly (and they are, it must be said, very tiny, brief instructions) , plugged the lead in, watched Windows XP go through the motions of recognising it, waited for the 'your new hardware is ready to use' message and then found that neither my sequencer nor Windows XP had this lead selectable for MIDI input or output. As far as they were concerned, the midi input/output did not exist, although other existing alternatives such as the MPU401 type MIDI in/out on my old soundcard were still being offered.
Upon re-reading the instructions I realised that the first described step was to plug the MIDI IN and OUT into a midi device and it turns out that this IS important. The chip inside the bulb in the middle of the lead seems to be a multifunctional USB audio/MIDI device and if it doesn't have a live MIDI device plugged into it on the MIDI side when you first plug it into your computer, the MIDI interface part of the lead may not be recognised by the install process.
To get out of this I had to system restore back to a recent restore point (one saved prior to my attempted installation of the lead) and this time I made sure the MIDI cables were plugged into my synth and the synth was turned on FIRST. Then, when the lead was plugged into the USB port of the computer, roughly the same 'new hardware found' messages came up, but after the 'your new hardware is now ready to use' message I found that I could now select 'USB Audio Device' for MIDI input and output.
Tested briefly with Quartz AudioMaster Freeware and this unit seems to work OK with that.