This was the last one I made, but it was almost two years ago. I see that you didn't use the same jelly roll around the square. I think the magic square suggests to sash each block completely with one fabric, then overlay one block with another cut and sew ( or sew and cut, can't remember!). Then that little corner won't matter.
One problem I found with doing this with layer cake squares is that you need more than one jelly roll strip to sash each 10" square ( you need 2 10" strips and 2 13.5" strips which is longer than a jelly roll strip). So I cut my squares smaller, so I could get the one jelly roll strip to sash one block. Plus I thought the 10" square made a pretty floppy block. I think the one I pictured used a 8" block, which I had cut from yardage. Just something to think about.
Good luck with your project!