At least on my system
I restored a Windows MC28 Library backup on my Linux MC28.
I used find/replace library tool to change the windows path notation to Linux format, and replace the drive letter with the base path to the files.
I entered settings, changed all the settings with paths to their Linux variant on my system.
I ran import and it looked and worked fine. Audio plays fine.
The setting 'run auto import in the background' is turned on.
I had a view open based on panes with the base path of where files are located.
A few of my albums are a single file accompanied with a cue sheet. MC imports them as '\data\music\etc'. Notice the backslashes ...
I deleted them from the MC database, but after a few seconds this path re-appeared.
When I opened it to view the artist and albums, I noticed it is only the single file albums with cue sheets that do this.
When I selected an album, I saw a growing list of tracks for each album. Auto import was stuck in a loop, reimporting the cue sheets over and over every couple of seconds. After a few minutes there were several dozen of each track.
Deleting them had no effect, auto-import continued importing them in a loop. I disabled the import in the background and then it stopped.
I wanted to reproduce this without restoring the Windows backup, but when I closed MC, deleted the .jriver directory, and tried to restore the license it said it couldn't contact the server. Its been like that for the past 30 minutes or so. I'll try again later.