I hate to do this, but as Franson support seems to be virtually nil, I have a solution for you: http://www.eltima.com/products/serial-splitter-ce
For your info, I experienced exactly the same issues on my Pocket Loox 720 with WM2003SE. But most of the time, I could get it running after a couple of soft resets and reconfiguring GPS Gate. In January I broke my PDA and bought a new one, still a Pocket Loox 720. On that new machine, I NEVER got GPSGate to work.
Eltima Serial Splitter CE works differently, and for instance does not allow sharing of ports. But it allows you to free up unused ports and reuse them as vitual ones. It announces a feature to create up to 20 supplementary virtual ports COM0 to COM9 and VSP0 to VSP9. Of course, to make a COMx port virtual, it may not be assigned to a physical port.
Two issues however with Eltima: /2/ I can't find out how to use the VSP0 to VSP9 ports (their support says the software must be able to see them, but none of my softwares (TTN5, OziCE and GPSDash2) see them, and /2/ it's quite pricey.
But it works very well and I have junked GPSGate.
BTW, wondering if someone at Franson still reads this thread? Last time, someone from them posted here, was 7 months ago!