nevermind... in the known issues!
If I'm understanding you correctly, I don't think that's a bug. The FX button doesn't "click," it just lights if GigaPulse SP instances are there. If you open up the instance(s), you can mute them on the GigaPulse UI itself.
I have not seen the UI anomaly you're describing.
in the known issues the speak that this button does not work as of yet...
sometimes when i click on it, it graphically turns my "Q" button into a fx tab. odd.... screen redraws do not help.
no a big deal.
When I used the VST/Impuse insert the button lit up