[Zubersoft]

For anyone that references this post, I had forgotten about the file access restrictions in the Windows 10 version of MobileSheets. The Windows 10 version of MobileSheets cannot access files outside of the storage location unless the user explicitly picks it with Microsoft's file chooser. This means that the audio files referenced in a csv file cannot be accessed unless they happen to be in the storage location. So users who need to utilize this functionality need to make sure all of the files reside under the storage location before importing. 

itsme - I'm still investigating things based on your last email, so I'll post the results here once I know more.

Mike