Cursor Cooldown is an addon that provides a cast bar, global cooldown bar, swing timer and cooldown timers in a circular fashion around the mouse cursor or alternatively at a fixed position on the screen. A lot of addons mess with the default castbar. Cursor Cooldown doesn't do that.
If you find a bug or have any wishes for the addon feel free to write a ticket on GitHub
Should the toggle for it not work properly its most likely that another addon modifies it as well.
To open the options menu type "/cc"
Cursor Cooldown is a fork of an old abandoned project: https://www.wowace.com/projects/gcd It has been updated to work with BfA. Credits to bakahar, Finghin and Sancty for their previous work.