My slightly ill-fated project has finally come together. As you may remember, I got some of the blocks wrong and had to unsew them. Other mishaps followed but I managed to finish this piece regardless.
I found a leftover piece of batting that was exactly the right size, sandwiched the layers and used one of my sewing machine’s decorative stitches for quilting. The thread I used was Superior Threads Rainbows Col. 846 which was working great on all the different backgrounds.
Not a masterpiece in the end, but it’s off the list.