@firebelly Are you using r138? If so, it completely hosed the 1.4 CocoonJS launcher. I am getting a very similar error and all I did was open up my project and re-export it. It was working fine with r137. I think Scirra and Ludei just need to get in sync.
Just an update, I tried using r138.2 with the COcoonJS fixes, and I'm still getting a black screen with the error I posted above. Again, Ludei suggested it is because of Box2D being old. I don't know if the cocoonjs fixes in the .2 release were meant to address that.
If you're using CocoonJS 1.3, the latest build of Construct 2, and physics objects, you need to turn accelerated physics off in the CocoonJS properties. It's defaulted to on but only works in CocoonJS 1.4.