Sprite Stitch Board!

I really want to make some cross stitch buttons. I bought a set to make self-cover fabric buttons. Here's what it looks like:
You put the fabric in the green bit, place the button front on top of the fabric and gather up the fabric sides. Then you use the pink bit to push down the pin back. It works great for thin fabrics but I just can't seem to get the backs to fit on when I try with a fabric as thick as aida. Other people seem to have success with this but from my attempts I'm thinking they must be magic! Does anyone else have any experience making cross stitch buttons and any advice they'd be willing to share?

I just made some for the mini swap, and they came out okay. For me, it was nearly impossible to hold them in the air and get it all squished together properly - I'd only get half of the button and then it wouldn't stay closed up... Then I tried putting the whole set-up flat on the counter and pushing really hard. That works way better! The worst part was trying to get make sure they came out centered! Try to push just hard enough to see the indent of where the button will be on your fabric and adjust it before you finish the button if you need to. Hope that helps!