I believe there's some confusion here:
ParkMe was a Couatl *feature* we used in scenery, which enabled several kind of docking aides, some electronic like the Safegate, APIS, some hybrid like the AGNIS-PAPA (which is half optical and half electronic ), and some entirely optical, like the AGN, used for example at KDFW Terminal B
ParkMe also had the parking evaluation, but no marshaller, and it was available only at selected parking on FSDT aiports.
GSX improved on that, by adding the marshaller on every parking on every airport, plus it supports exactly the same kind of docking systems as ParkMe, nothing has changed with GSX, KDFW Terminal B STILL has exactly the same AGN system it had in ParkMe, which is a static optical system that gives only lateral guidance by means of parallax effect.
This is how it's supposed to work, and it hasn't changed a bit with GSX. If you want a more advance docking system at KDFW, go to a gate with a SafeGate system.