As for Cinemachine, indeed there used to be an unofficial integration package. To be honest though I never went into making an integration with Cinemachine officialy since the goal of Slate is to be as self-contained as possible without complications, especially in the camera direction department and the workflow for creating moving camera shots in Slate directly is quite fast and efficient, that I’ve personaly never had the need to create a Cinemachine integration for that 🙂
If you have any further question please let me know. : )