Hello,
Sorry to hear you are having issues.
To pin a folder to your Start Menu there are various way. Instead of pinning the shortcut to the folder. Why not pin the folder itself into a Start menu group or tab.

You can always search for the Universal app using Start panel search or looking it through your all program list. Right click on it and pick "Pin to Start menu (Start11)

Thanks
Basj,
Stardock Community Assistant.