Not having the exact same issues as you, but definitely having issues in this update. Preview is super slow and buggy. As soon as I use a textfield anywhere even on a basic test, I am getting the error: this application, or a library it uses, has passed an invalid numeric value (NaN, or not-a-number) to CoreGraphics API and this value is being ignored. Please fix this problem.in the console. Build times definitely seem soooooo much slower, its making the process annoying when it doesn't need to be.

I've cleaned the derived data, tried killing every Xcode process going, restarted a billion times lol. Great update this time around.