I am at the spiral level. I have connected the bridges and i found the mini model where I was able to slot in the missing bridge piece in order to access another tower. I am stuck now as the bridge to the final tower is missing and while I can see a switch over there, I have no way to get over to it. I am really stuck with this one.
To solve this, you will need to go back to the small model and use the same solution you used in the previous level with the bell. You can interact with the switch on the far away tower on the model. This will cause the final bridge to appear, connecting you to the final floating tower