As I’m new to writing scripts, perhaps something simple, but I’m having trouble.

I have this sample sheet. There is a “Monitor” that I’d like to change between full frame, 4-box, and a 9-box configuration. I’d like it to merge or un-merge the necessary cells based on the value returned from the drop down box in cell ’04’.

(https://i.sstatic.net/2fa1RaVM.png)

Link to Sample Sheeet

Thanks