I just imported Slate in project based on Unity 2018.1.6.f1 and I have the following error:
“Assets/Plugins/ParadoxNotion/SLATE Cinematic Sequencer/Directables/Tracks/Runtime/Actor/AnimatorTrack.cs(32,11): error CS0246: The type or namespace name AnimationPlayableOutput' could not be found. Are you missingUnityEngine.Animations’ using directive?”
In the current/latest version of Slate, there is nothing in AnimatorTrack.cs line #32, or even remotely close to that line 🙂
Do you by any chance had a previous version installed? If so, please try a clean re-install by deleting Slate folder and re-importing the package anew.