I have the LR CC classic 7.4 and for the last several versions I can't get the user preset in the develop module to stay when I select it. As long as I hover over it after selecting it changes to the preset but does not stay when I move the mouse cursor off the preset I am selecting.
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[Moved from generic Cloud/Setup forum to the specific Program forum... Mod]
Hovering over a preset shows you a preview. No offense, but did you actually click on it to apply it?
If you then hover over another preset it will of course show you this preview.
You can turn off this behavior in the preferences.