File explorer has a bar at the top which shows the file path, you can type file paths into this field.
C:\Users\"your PC username"\AppData is the true file path.
C:\Users\%USERNAME%\AppData serves as a shortcut to bypass clicking through all the folders.
View attachment 4807836
If you paste : C:\Users\%USERNAME%\AppData\LocalLow\KsT Games\Seaside Mystery into the prompt at the top of file explorer, it will take you directly to the correct file location where you will find system.smg, or be able to create it. Or, you can browse through the explorer to find the folder yourself. This is not that complicated.
To create this file, simply right click > new > text document. Rename the file to system.smg. That's it.