What 3DS Max version do you use ?
For Max 2022/2023, please check if the RailClone folder is created at C:\ProgramData\Autodesk\ApplicationPlugins.
For previous versions, check for "railclonelite.dlo" in the 3DS Max "plugins" folder.
We changed recently the installation format for Max 2022/2023, and we want to be sure it's working well.