I had to create mapscaler script to fix scaling issues with the JMP maps, and for that I had to figure out where all the map files are. There are two possible locations (I assume this is still true for JMP19) I did something like this (for windows)
Names Default To Here(1);
mapdir1 = Convert File Path("$JMP_HOME/Maps/", windows);
mapdir2 = Convert File Path(Word([1 -3], Get Path Variable("$HOME"), "/") || "/JMP/Maps/", windows);
show(mapdir1, mapdir2);
I also slightly expect this to break at some point
-Jarmo