Hi.
It's a shot in the dark...
 
Serial device is Windows interface, right?
maybe you have to have the Microsoft Wavetable device output ON
for the serial port to pass thru?
Or run under MME/WDM?
Perhaps the interface is not seen under asio.
 
Peace.
Mel

OldTimerNewComer
Perhaps the interface is not seen under asio.

ASIO doesn't really enter this, it's audio only.

I think the clue is in the part where Windows is reporting it as "unknown" 
This tells me the drivers did not install properly and I would put my money on the 64 bit system not having a proper driver. 
I'm not sure why your worrying about the 5 volt thing. 
Midi is data and as long as it gets there in one piece myself I've never worried about that fact other than being aware that using a Y cable can blow things up. You always use a midi merge box to combine, or the thru port. 

Hi,
 
hmmm, i'll google that "Microsoft Wavetable device output ON" part for sure. Another thing i thought about was if there exists some kind of intermediary software that can act as a virtual midi device (inside Sonar) and route signals out to the serial midi-port (since windows can see it alright). I need to google that too. The drivers are supposed to support windows 7 (64). It feels like Cakewalk left something out of their 64-bit versions. I could also try to install the 32-bit sonar (using virtualization) to see if it shows up then.
 
The +5v is important since i recently bought the dsp-Gplug (which is supposedly the worlds smallest VA synth). It is basically a 5 voice, 3 DCO paraphonic syntheziser inside a midi plug (i.e ridiculously small). Iv'e had some problems using my usb-interfaces (m-sport 4*4/2*2 and E-mu 0404 pci midi). I can run it connected to my old jx8p but would like to leave the midi-out on that one for other purposes.
 
Thanks