If the properties of the event are not changed at all, the system will use the font as indicated in the FontLocation.
If the event handler changes the path, the system will try to use the indicated file. Please note that changing the system font name takes precedence. If you want to explicitly refer to a font file, please leave the font name untouched, or set it to null.
If the font path was changed by the event handler, and the indicated file could not be loaded, a new ResolveFont event will be issued. This event will have FontLocationUnresolved, and the FontPath will indicate the improper file.