Got the exact same issue as well.
Installed GSX last night and tried to test it today, but whenever I try request anything, it starts, and then that message comes up.
I saw in another thread that under %APPDATA%/virtuali/couatladdons there should be the following:
[gsx]
disable = 0
Mine does not have any gsx listing, so I added it, but it did nothing, still getting the error.
I as well tried running the live updater, but didn't help either, still getting the same error.
I have attached the error it produces, but to the simmer it is a useless error report as I have no way to know what is causing it - hopefully it can make sense to FSDT.
Kevin