I’m happy to announce that I’ve found the solution! Marble game (only one level) is solved with 30 steps and the program runs only 173734 iterations!!! 
You can try to decrease the limit (now 30) and reach the solution quickly… but be aware, you may not find the solution at all.
Donwload: marble_game.zip (1.3KB)
$ php marble_game.php
And wait… 