Please update retina.js, since there's some bugs corrected in the meanwhile.
Inside jquery.plugins.js you have Retina.js v1.1.0, but it goes right now on v1.3.0.
For example, it fixes a problem that resizes hidden imagens to 0x0px: https://github.com/imulus/retinajs/issues/97
thanks a lot for the information. We'll update it soon