I am having issues with the new upgrade to Photoshop CC 2015 on Mac El Captain. The only thing I did was upgrade from a working CC 2015 to the new version. Using the liquify tool give the following look. There is a box around the area liquified that is lighter than the other areas. When I turn of Use Acceleration in Graphics Processor, it is better but .... I didn't have to do this in the prior version i.e.. Yesterday.