Are you talking about other notes and folders within your vault, or stuff outside of your vault?
If the former you can add "[[Your note]]" as the property value, and it’ll link. If it’s to other files outside of your vault, it sure seems like the pure file link works as expected. I’m not sure if you’re able to alias those links though. At least I’ve not found an easy way to do so in a quick test round.
But I did succeed making a file link as a property value like: file:///Users/username/Downloads/filename.png