No fix on Unreal engine 4 stability? editor got very slow since 4.6 . Please fix problem with bug report: UE-6354
which got discussed here:
questions/142775/ue-46-only-extreme-editor-lag-and-mouse-jitter-whi.html#comment-142775-form
best regards. 
No fix on Unreal engine 4 stability? editor got very slow since 4.6 . Please fix problem with bug report: UE-6354
which got discussed here:
questions/142775/ue-46-only-extreme-editor-lag-and-mouse-jitter-whi.html#comment-142775-form
best regards.