Layers/Tracks of Global Part is very useful.
But I found that Layers/Tracks of Global Part can’t operate during the Song playing.
For example, when I play a song, I want to change some parameters of Fx.
I click Global at Song area but I can’t open because the song is on play.
It will be more useful if Layers/Tracks of Global Part could operate even the song playing.
Are there any tips?
Global Part is a Part only, it dows not include TRACKs. The Global Part exists in parallel to the active Song.
As such, the Global Part works on Part related assets such as Layers and Stacks, but not on Song related assets such as tracks and Notes.
“Fx” - Which ones?
Oh my god! I used wrong word. I apologize.
I mean STACK.
Such as insert effect, send Fx or even volume control of Stack.
You are doomed! 
Ah ok, now I see. You cannot select the Global Part while transport is started, got it. Will be fixed with the next version, thanks for reporting!
Exactly!!
Thanks!