Thanks for providing the link!
I just had a look at it, and this seems to be a bug in AIR. For some reason, Starling receives mouse coordinates that are totally out of the bounds (x > 10 Mio) of the screen!
A simple workaround for now is for you to activate Multitouch:
Starling.multitouchEnabled = true;
Add that line BEFORE creating the Starling instance.
I will forward the error description to Adobe, and will see if I can perhaps add a workaround to Starling, too.