Well, I'm happy to report that I fixed the problem. Now I can back hand the secret passage shot well and it makes it around the loop much more often. My guess is that when I straightened out the slight bend in the guide at entrance, that resolved it. Also, directly behind the bent section of ball guide (where I circled it above in previous post), there is the ball stop plate. I removed one screw closest to ball guide (circled in pic below) and installed a hex nut under the screw (like a washer would go) to act as a support for the ball guide. I used a longer wood screw of same diameter to do this. Before I did this, the ball stop base was actually under the ball guide (see second pic) thus not supporting the guide and allowing it to bend inward. Sorry I didn't take a pic of this. But hopefully it will support the ball guide from now on so it doesn't bend inward. Other than that, I just straightened the guide that was leaning to the left farther up and widened the secret passage lane a little bit. So it appears to roll more freely thru there now.
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