Just started using the workflow - great so far!
One very minor note - the convention for Toggl's own app and web interface is that when the timer is not running, the icon is grey, and when it is running it's red. Using your workflow, all of the icons are red, but the running task is green. To be honest, I think I prefer your use of color scheme (though it might be rough on someone that's colorblind), but having come from using the app predominantly, it threw me off a bit.
I'm not sure if there's anything actionable in this comment, but just thought I'd bring it to your attention.