Well I was wrong, navdata has nothing to do with it. I completely removed and reinstalled the XP11 IXEG install and updated Gizmo, and I found that like the others, it works if I load IXEG first but it crashes if I load any other plane first (even default X-Plane aircraft) and after a crash, the reload aircraft command from the developer menu gives a working IXEG.
GizmoLog.txt
Log.txt