Root Actor can not communication to nested actor

[Jinghang]

Dear LabVIEW users,

I need help on the actor framwork communication between root actor and nested actors. My code attached (LabVIEW version 2018). 

There are 3 actors in the system: Configuration, Status, and GUI

I want to use GUI actor as the root actor to launch Configuration and Status. I added some simple functions for testing purpose. However, every time when I want to send message from root actor to nested actor, the program will get frozen, for example, when I click any button in GUI Actor Core.vi, the program will get frozen and has no response. 

Can someone please let me known what mistake I have made? 

Thank you so much!

[Jinghang]

here is the screenshot of the root Actor Core.

the logic is so simple, and I don't know where is the problem. for example, when I click Stop button, the whole program will get frozen, and I have to close LabVIEW to exit the program.

Can somebody help me? thank you so much!

[Jinghang]

here is the new (simplified) rar file for the program. 

Thank you so much.