We are not able to reproduce this issue.
Does the first problem already solved by re-exporting the content? (“Song Play Error /Settings File Error”)
To reproduce the issue and find a solution we need to have your content from your USB drive
I’ll send you a dropbox invitation please zip your song(s) and playlist(s) with containing folders and subfolders then upload to the dropbox folder. Please also send us a step by step instructions how to reproduce the issue we’ll update you about our findings.