Sounds like maybe your X-Plane directory or sub-directories, e.g. Output, may have been set to read-only by Windows. But I don’t see any complaints in the log. Could you PRIVATE message me your e-charts.cfg, please?
It’s actually using their own implementation (by OscarPilote, of Ortho4XP fame) that was originally done for their new Falcon 8X project, so looks totally different (wrong) compared to the G1000’s.
2022-02-05 20:39:41 CL650[alm.c:152]: Unable to download GPS almanac from https://navcen.uscg.gov/?pageName=currentAlmanac&format=sem: Couldn't resolve host name
Looks like your DNS blocked too, as you suspected. Google DNS has no problem resolving the site: https://dns.google/query?name=navcen.uscg.gov. Are you sure something else isn’t at play on your PC/network? Anti-malware or something?
Deleting the CL650 directory from Output will reset your user settings including any charts service selections and authentication data. You’re 100% sure you reset your settings afterwards?
Also, clicking the “visit” button isn’t what brings up the authentication page, it’s the act of turning on the power to the FMS(es) and it determining an (re)authentication is required.
No, it uses X-Plane 11.50+ format from Custom Data directory.
If the data is correctly installed in this location (check cycle_info.txt) then read the FMS Primer document provided either the plane for more information about selecting active nav data.
I assumed OP meant the former, but I guess the latter is possible. I agree it would be unusual, there may be cases of using an old HDMI with limited bandwidth or something. ¯\_(ツ)_/¯