Tried my darnedest...
... but gave up on level 10, because I found a perfectly "legitimate" way to cheat that the system somehow picked up on and failed me. So check this out... I shrunk the browser window until it was so small vertically that the bottom scroll-bar basically cut the START and GOAL boxes in half. Once I clicked on START, I took my mouse into the scroll-bar area, was able to get all the way to the GOAL area without tripping failure, but then as soon as I moused back into COMPLETELY SAFE mouse territory (right on the GOAL button, in the red above the button, or to the right in the black) the game tripped. It seemed so right that that be a way to defeat it by cheating... what happened?