Normal CocoonJS export and every other platform/preview combination work as intended.
However ONLY when using Preview over Wifi to preview directly into CocoonJS, some collision boxes are skewed or displaced.
For example collision starts 20 pixels BELOW the bounding box of some objects.
This is very hard to reproduce and I can't make any simple CAPX where you reliably see the issue every time.
I can reliably reproduce it in a game I'm making, but I'd rather not put out a CAPX of that - I can send you link on a private message if you want to look into it.
Construct 2 version:
R139, CocoonJS 1.4