Hey @nick - Yes, I learned about the "sample code", as it will warn you and request that you reload the code - if some how you were allowed to edit it, which I think you are trying to prevent - which is being overzealous. Luckily I was able work around the issue I was having.
Basically - if you attempt to edit this code, it trying to lock you out, but at the same time, there must be a bug somewhere that keeps the lock in place when you are trying to type outside the sample code. Anyway, I had to completely clear my cache, quit the browser, log back in, and then it let me add to the code.
IMHO - Sample code should not be required, but allow one to edit it if they see a better way. I understand the who learning thing, but when I was showing my son (who is still learning), I was showing him it did not matter if you changed variable names, how you should not quote variables, etc.. Being able to edit this code is important learning, EDGE method.
You should give the option to reload the sample code, but do not require it (I know this is a feature). Of course, do not allow (which I see happening is some code..) capabilities not yet achieved, ie the use of loops or object detection sub-classes.
I love the game! Keep up the great work! I am a stubborn full-time programmer.. working with my son, challenging him to keep up with me, and teaching/helping him when he runs into issues.