Concerning the partitions, AIUI and IIRC on the edmini V2:-

      partition 1 (about 1 GB) is an extended partition containing 5 to 9
      partition 2 (rest of disk) is user data
      partition 5 (about 128 MB) is swap so backup is not necessary
      partition 6 (about 8 MB) is raw uImage
      partition 7 (about 8 MB) is initial ro rootfs
      partition 8 (about 128 MB) overlays rootfs later
      partition 9 (rest of extended partition: about 752 MB) contains personalisation and updates