GSX doesn't use any specific keys, or try to read the keyboard directly. It will use whatever key is currently mapped to the Slew Events in the simulator. In the case of what is *commonly* mapped to the Z key, GSX will use what is currently mapped to the "Slew Down (slowly)" command in the Controls Page and, this Event can be either:
- Used by another Add-on. Check that.
OR
- Changed or disabled by yourself using the Slew section of the Controls page.
OR
- Be different in some countries ( German keyboard have the Y and Z keys reversed )