I can't say I have ever heard of it.
If the file is "Map.gsm" then it is an object that should work in 20, however there were some GDL commands that were deprecated in version 20 so they no longer work as they did in previous versions.
You will get error messages when you try to use it (assuming you haven't turned off the reporting feature in the Work Environment).
I just did a search in the object settings and this was in BIMComponents.
Is this it (map grid)? - it does work in 20/21 but it is just an adjustable grid.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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