Jacob but it works if is called from the search bar?
If you will press defined shortcut on a keyboard, not mouse, will it work?
Also, I've added a speed command on %400 and sometimes when I add it to the clip it adds a [%400] next to the clip name but sometimes it does not actually apply the effect.
What kind of clips are you applying speed command to, when it doesn't work? If you will do it manually (open speed dialog and change values there), will the result be different?