The icons are in the resource DBADVNAV.RES, so, replacing this resource with your images in this resource should do it.
Will I have to recompile the resource? What should I do after replacing my images in to the dbadvnav.nes?
It should be sufficient to recompile your application that uses this resource.
what does that property "GlyphResName" do? Could I simply use it instead of recomiling the whole source?
This is in case you would add additional images in DBADVNAV.RES with a different name rather than replace existing images and with GlyphResName you set a custom suffix for the images that were added to DBADVNAV.RES.