The override turbulence option limits the REPORTED METAR wind speed to 10 knots and removes gusts, to limit the injection of X-Plane turbulence, which will result in a better experience regarding ASXP turbulence. Without overriding, you'll get predominantly X-plane based turbulence that overrides ASXP's. The ACTUAL wind speed experienced as injected by ASXP should not be confused with the REPORTED METAR wind speed/gusts. In other words: The limited speed is only for the "data" X-Plane uses to determine it's turbulence calculation, and the injected wind speed is separate and always should be as shown by ASXP debug screen.
We found that sigmet/airmet sub-area determination was not working as expected, resulting in much smaller areas than ideal. We're working on improvements which should be in the next build to make these sub-areas much larger and result in more expected turbulence levels in such areas. We still recommend leaving Override X-Plane turbulence ON, but we leave this DEFAULTED OFF because it does alter the reported surface wind speed/gusts and users should be aware of this before checking it.