If you have problems finding tools for the SD copy stuf I can recommend [Only registered and activated users can see links. ].
Does the same like these tools to clone your hard drive but for SD and USB.
If the SD shows up in Explorer as a drive that program should be able to create a backup.
So if Home changes anything on the SD to make it work/visible you can put the backup on with this tool and see if it does the same again.
Might be worth trying to copy the untouched SD first this way onto a new SD and see if the copied SD works.
But again: if this works it only works with an untouched SD that never was used in the car or "acivated" with Home!