I think I may be having similar issues with the mouse camera. It starts off okay but in less than a minute or so into the game as you navigate with your mouse, it will suddenly snap to a particular random angle when the mouse is scrolled past a certain angle.
Funny thing is for me, this problem never arise while playing in C3 mode, it only happens after exporting to nw.js format. I tried using different modes while exporting, eg. kiosk mode, resizeable windows, window frame, etc but to no avail, as problem still persists. Again, the problem happens only after it is exported. No such issue when playing in C3 browser mode.
Judging from the number of people having similar issues with this, I think C3 people should seriously find a solution to this problem.
I have attached the camera event action as follows.