Here’s my solution (it’s the one from the book):
And here’s the link:
http://www.lodev.org/jstumble/?board=rrereree0ereelleler0ereelrelererleelexeerelreerleli
Description: Very similar to puzzle 19, except in this case, the only way you can get a blue ball over to the right flipper (in order to release a red ball) is by having both bits pointing left to start. The image below shows the path of the ball when both bits point left: