I think you're talking about two different issues here. I understand what you're saying, that there might be an error underneath... but the error message was specifically telling me there was already a link set up and there was not.
Wrong error message.
Happens on the first "save" of the info.
No link is present. There should not be an error message telling me the disk path is already in use when it is a fresh install and I've literally just hit the save button once after entering the info for the first time.
If there is an error it should be a different error message.
The error that we're talking about here (platform_title, url_path, etc., must be unique) have their origin on your database level. In other words, there's only two scenarios where this error could be thrown: A) There does indeed already a record with these values exist, likely from a previous (failed) attempt to establish the link or B) your database is malfunctioning.