Flying the ILS34 at LOWW using the gaya LOWW scenery, you’ll notice nearing the threshold the PAPI showing 3 white. If you correct down to a 3 degree glidepath, the GS for the ILS will show you way low (you’ll get GPWS GLIDESLOPE warning). Is this something GAYA must fix, or can navigraph see into it to correct the TCH for 34?
Likely this is an issue with the installed scenery.
To test, isolate your community folder and test the glideslope with the basic Cessna 172. If the glideslope shows normal behavior, it would be something to bring up with Gaya development.