I've had this problem ever since NW 0.10.5 all the way to the most recent I can test it on, 0.13 to 0.15.
This is an old problem: https://github.com/nwjs/nw.js/issues/3307
I was hoping it would be fixed eventually but it seems to be an OSX limit on the number of files (images loading) opened at once by Chromium.
I wanted to ask if Apple or Chromium is aware?
Develop games in your browser. Powerful, performant & highly capable.
It's been an open issue on githib for a year now....
I don't hold my breath any more. Sorry...
It could be an equivalent to the Windows "10000 is enough for anybody" limit on OS X, except by the looks of it, a lower limit.
I assume Apple are aware of any limits in OS X but presumably won't change them, and AFAIK nobody has tested Chromium and there is no bug report at crbug.com, because the focus has been on NW.js.
Not much we can do with this post here, and it doesn't follow the guidelines and doesn't relate to C2 itself, so closing.