Someone else will have to comment on the errors sorry!
But can help with this:
If the 'front' edit was passed automatically, it should instantly appear.
You don't have to wait for the original cover art edit to be approved either if you go to:
Picard > Options > Cover Art > (hit the v next to Cover Art) > Cover Art Archive
And then untick "Download only approved images"
By the way, in this release:
The second image should be types: front, spine, back
And the third should be: medium (definitely not liner)
On the other release the second image can be markes as: back, spine
Thanks for your additions and hope someone can help with your errors!