[Zubersoft]

So I had some time to finally look into this. If you use an SD card with "Let MobileSheets Manage My Files" unchecked, MobileSheets is not going to have write permissions for the SD card folders. That's just how the Android OS works now with the restrictive SD card access. However, you can get around this by going to Settings->Storage->Set the MobileSheets Storage Location, and setting it to the root folder you plan to use, or even the root folder of the SD card (/storage/0000-0000 on some devices). Once you do this, now MobileSheets will be able to write to the SD card folder and everything I described above should work. I verified this on my own devices, and it did not work properly until I set the storage location to the root folder of the SD card. Sorry it took so long to get you this information.

Mike