Some people may find themselves not being able to open their map. It will cause an error. These are the two commands to use (For Shadowlands, and for Rubi-ka) to fix this little glitch.
/setoption PlanetMapIndexFile normal/PlanetMapIndexNormal.txt - This is for Rubi-ka. Copy paste this into your AO chat and it will set your map back to default, there for allowing you to change back to your 3rd party map and fixing the issue.
/setoption ShadowlandMapIndexFile Shadowlands/ShadowlandsMap.txt - This is the same deal, except this is for when you have problems with your Shadowlands map.
I hope this helps fixes your map issues