I’m not sure if this will help or hurt, but maybe you can glean a bit of info that might help. I use parameter drivers in quite a few places, and I’ll show you what I do with them below.
I use them to do random twitch animations on occasion whenever I change a gesture on my hands. I have two variables declared in both my Parameters file and my layer: ‘RND’ and ‘Twitches’
RND is used to determine IF I should play a twitch, and Twitches is used to determine WHICH animation to play.
Whenever a gesture happens, I have a default transition with an exit time (No parameters) going to my ‘Set Twitches’ state, set as local, which generates a random number for RND.
In another layer (Please excuse the mess), I test the value of RND and Twitches. Ignore all the other stuff here - it’s not necessary to know what it does - just focus on the highlighted transition. I only want a twitch to play if there isn’t one already playing.
If RND > 75 and Twitches is 0 (No animation) then I’ll again randomly set the Twitches variable to a non-zero number and let the transitions figure out which one.
Once my animations complete, they transition again to a state ‘Reset Twitches’ which sets both the RND and Twitches variables to 0.
Again, I’m not sure if this will be helpful at all, but I figured that maybe seeing all the values of some working drivers might reveal something. All these layers on on my FX controller, so that might be a clue too, I don’t know. 