Level 14 through me for a loop as it was the first level that required speed. I tried several different set-ups, and this is the one that worked best for me.
How to Solve
The problem: create a red-green quarter-circle, and supply enough of these so that you’re supplying 8 per second.
This is my solution:
1) Color the circles first. Find an area where you have quarries of red and green near some plain circles. (See my picture above.) Create two paths from the circles towards the HUB, and color one path red and one path green.
2) Then combine the two paths using the Stacker tool. Assuming you are facing north, have the green circles on the left input and the red circles on the rightmost input.
3) Finally, cut the circles into half so that you create two lanes from one. Using the two variants of rotation, one on each lane: rotate the halves so they are facing upwards like watermelon smiles. Then cut them in half again. Use the CCW Rotation only on the 1st and 3rd lanes. Now you have 4 quarter-circles from one circle!
4) Connect all your lanes together using two balances then one balancer, and then send everything to the HUB! You win!