If you are looking for a "helpful guide" on how to actually the game once you have it running:

: Files ending in .rar from third-party sites can sometimes contain malware. Ensure you are using a trusted source and scan the extracted contents. The actual game file inside should be a large .nsp file.

: Downloading "NSP" files for games you do not own is considered software piracy. To stay within legal bounds, users typically "dump" their own purchased games from their personal consoles. Getting Started with Railgrade

: Railgrade , a management sim where you build railway networks to deliver resources and restore an industrial colony.