These files do not work on a standard, "out of the box" Nintendo Switch. Your console must be running Custom Firmware (CFW) .

If you enjoy tycoon and management games, Railway Empire is frequently on sale.

You can back up your progress to Nintendo's servers.

Connecting a modified Switch to the internet often results in a permanent ban from Nintendo’s online services (eShop, multiplayer, and system updates).

This indicates the file includes seven "Downloadable Content" expansions (new maps, scenarios, or trains).

Are you trying to with a file you already have?