I am suffering the same with RAW files CR2
I signed up for the photograpy package 2 days ago after 2 wk trial of PS and LR without problem. LR reloaded and goes non-responsive after a crop and I try to move on to a different image. PS CR goes non responsive when I try to load image after adjustment. Feel strongly have a problem with the release. About shows 2015.1 and CR 9.1
Turn off the GPU (Graphics Acceleration) in LR / Prefs / Performance and see if the slow-downs clear up. One of my two computers has an older video card and LR's GPU acceleration is slower than the CPU so I shut it off to keep things from becoming choppy.
It is already off, so that's not the problem.
Thanks for the suggestion
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