Hello Ken,
Have you got any answer from support about this issue?
It looks like I'm facing exactly the same problem as you with this TGS Gauge (I can see the gauge but the screen remains desesperately black when taxying).
I have also spent time trying to solve this problem without success. I'm just with FS9 and not FSX, but I'm convinced that the cause is a same origin.
Thanks for your help.
Kind Regards,
Marc