The possible insert

Well here's what I'm proposing to do to add to the final round. I'm also showing you what it's going to be backed onto as well so you can see my conundrum!!! 

I'll sew these inserts on (if that's what I decide) and then put the backing fabric wrong side up on the table. I'll then fold the sides of the backing fabric upwards and tuck them under the EPP cloth. This'll all take a lot of mumbling and grumbling and accuracy but hopefully very little of the backing will show on the finished piece. We'll see - this is still just speculation!!!!