Huh, odd... I'm afraid to investigate further you'd have to ask the game author to trial a non-minified version with you. I'd be keen to find out the cause so if there's an issue in Construct 2 we can fix it.

Actually I did some sleuthing from the minified code and found where it corresponds to in our engine. It's just calling a tick function on one of the behaviors, and I guess from the error report it's calling a function on an array with an empty element in it. No idea how that could fail or why it would only happen on one system and not another, this is probably only Javascript logic. Maybe the author is using an old version of C2, or a broken third party plugin... or you have a buggy extension that runs in incognito mode?! I still want to get to the bottom of it, maybe if you head over to our forum at www.scirra.com/forum and post there we can dive deeper.

If you want to try to resolve this, feel free to contact me via email (shawnsmlee at gmail); the code/capx project file is also on my github, so if you would like to try making sense of it yourself, you're more than welcome!