installation 

1. put the plug-in file from the plugins folder ziRail_XXXX.mll and ziWireframeViewport_XXXX.mll to the C: \ Program Files \ Autodesk \ MayaXXXX \ bin \ plug-ins \

2. Copy all files (folders and py files) except the plug-ins folder to C:\Users\YJ\Documents\maya\2020\scripts

3. Open Maya and run it in the python tab of the script editor:

import zi_rail

zi_rail.main()