Elevator Solution

Your objective is to move the balls from the outer ring into the two cups at the bottom. Note that the left cup has a red marking and the right cup has a yellow one. Accordingly, you must drop the red balls into the left cup and the yellow balls into the right cup.
The large outer ring is rotated by pulling the weight on the right. The inner rings are rotated (either clockwise or anti-clockwise) with the two gold buttons in the middle of the rings. The buttons rotate the inner rings as follows:
Left inner ring top button: anti-clockwise
Left inner ring bottom button: clockwise
Right inner ring top button: clockwise
Right inner ring bottom button: anti-clockwise

Balls drop from the outer ring into hole (1) on the left inner ring
Holes (2) and (3) are common to both inner rings
Hole (4) is used to return balls into the outer ring
Hole (5) is used to drop balls into the cups
The first ball drops into the left (red) cup, the second ball into the right (yellow) cup and all subsequent balls follow this same alternating pattern. You always know into which cup a ball will drop from the position of the latch as illustrated in the diagram.
If a ball is dropped into the incorrect cup, use the green button in the bottom left corner to empty both cups and start over again.
Although you can manipulate several balls within the inner rings, the explanation below shows what to do with one ball at a time. I suggest that you do likewise until you get the hang of it. If hole (1) is empty, pull the weight and a ball will eventually drop into it.
If the ball in hole (1) matches the colour of the cup into which it will drop, move it to hole (2) or hole (3) using the buttons on the left inner ring. From here move it to hole (5) using either button on the right inner ring and it drops into the cup.
If the ball in hole (1) is the incorrect colour, move it to hole (4) using either of the left inner ring buttons and it drops back into the outer ring.
After dropping sufficient balls into the cups (note that you probably won't use all the balls) they both lower and then rise again. Now pull the lever on the right to activate the elevator.
The wooden lever on the elevator is used to operate it.