I fixed the ring connector of NM1184's chimney Gravitrax extension. The model is great: if a ball pushes the leaver on the base tile, the chimney instantly releases up to 10 additional balls! 

Changes:

The initial model presented a challenge for printing as the connector socket required a considerable amount of bridging, resulting in unnecessarily extensive cleaning and consequently requiring additional time for assembly. Therefore, I followed maskedmarble's suggestion to remix this. I really like andy40's connector, so I used it here as well.