I see what you mean. Doesn’t work.
I have had peculiarities with material time before. For instance, there’s a difference between the way the time node works in the material editor, and how it works in the level.
No matter though, because you can get the effect you want by just multiplying time.
If you want to change the speed, stop it, or make it go backwards etc, this can all be done by just multiplying it by a parameter.
Is that any good?