Nothing fancy, just a stick with a bum on the end, that stick through the stand. I pulled as far as I could, fixed it with superglue an cut the excess. This way the figures can still be removed.
Pictures there to help proper assembly.
Update: Mostly compatible with the quidditch set, but some needs some tinkering because of small hole on the feet, and Luna has no hole at all.
The author marked this model as their own original creation.