Could be related to a similar OpenCL bug in Photoshop with the El Capitan Nvidia web driver. During the beta phase if you tried to resize an image significantly in Photoshop you would get a blank black image as a result. With the final drivers Photoshop simply crashes. Adobe says it's an OpenCL bug and recommends disabling the API or graphics acceleration in the app's prefs. If you could do that in Aperture it might solve the problem.
I don't know who out of Apple, Nvidia or Adobe (least likely) is at fault.