I'm sure you've seen this, but here is the link anyway.
It's the Finnish guys who do indoor towing of very small and light gliders. Their release is as simple as it gets. There is no release! It's just a piece of rod, CF probably, set 90° to the fuse sideways and they hold a little rudder to keep it on, then turn the other way to release.
Their gliders are very light and run about one meter span. My Vampyr is planned for about half of that. They stick to 1/15th scale, my Vampyr is 1/20th.
I don't even know what the scale of the Zoegling is, but it's really small.
Still haven't glued two sticks together even though I've got a lot of cut parts.
Got to get my Dremel driven bass wood stripper working.