it takes minutes to change from 1 to the other picture, too long to edit something, but when i open lightroom 5, it all works fine. I optimised catalogus already and just need a solution, have no clue what is causing the lag.
[moved from Adobe Creative Cloud to Photoshop Lightroom]
If you have the GPU enabled in Lr CC then disable it to see if performance gets better:
Also, are you running the latest release Lightroom CC 2015.4?
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