This is because a KMZ file is not plain text file that can be viewed in Notepad. Instead, a KMZ file is a compressed archive. You could uncompress it with unzip but there should be no need to do that.
In my conversion utilities I include a link...
In waypointmap.com he is generating a DJI-compatible KMZ file comprised of "template.kml" and "waylines.wpml" containing the WPML language for DJI drones. Waypointmap.com will work for DJI drones if you desire to create mapping missions.
A...
DJI has made it clear that they have no interest in providing MSDK support for the Mavic 3, however, their recent addition of Mini 4 Pro support to MSDK v5 gives us a glimmer of hope.
I have created a work-around for those with a Litchi account...
I just heard back from the Litchi developers about the questions I listed above.
1. Yes, they will add support for the Mini 4 Pro to the Litchi Pilot app.
2. They will provide both "Virtual Stick" and "Native" waypoint support if they can.
3...