If you use Type: Command, the output is always [\r\n]+.
If this is not the case, there must be a conflict with some other commands/settings.

Pressing Shift+Win+V shows a msgbox only - no Windows Start menu.

Don't know, I tried on three computers and it works fine for me.

Try increasing the Paste delay in Preferences/text Expander/Advanced. Any difference?

Your command simulates the mouse clicks on the desktop which may trigger various effects, dependent on your setup. Can you try the same shortcut with the simple command like to see it the issue is related to your command?

Sorry, no idea what you are trying to do...

Sorry, what is the Google Autocorrect shortcut and how is this related to FastKeys?

Interesting, I tested the shortcuts with Win key and all work without any issues. The exceptions are Win+L and Win+U which are locked by the system.

Tried Shift+Win+Q, Win+E ... they should all work fine.

Sure, see the setting under Preferences/Text Expander/Advanced - Use Clipboard if text is larger than...

This is always the case. From the documentation: List may contain full or partial window (application) names.