Place the map file after you download it, in the map folder after the name.
C:/MicroProse/Mechwarrior3/zbd/then folder "c1-c4b, and t1") Bold print is the folder where to stick the map.
Solar Terrors Training Arena Folder: t1 "very small arena for clan deathmatches)
Solar Terrors Basic Training Folder: t1 "very small training grounds for very new players"