How to change Container Color

Sorry guys, absolute beginner just starting. I have the latest build of Touch Designer but trying to follow a Yale Workshop tutorial series from 2017 with an older version…

youtube.com/watch?time_cont … FKkhRG9AcY

He changes the container backgrounds using parameters window
Container 1 to Orange, and Container 2 to Blue.

I literally did exactly this, and my containers are still both solid default black. I notice the newer version has tons more options than his. What other steps do I need to do?

make sure you also change the Background Alpha from 0(fully transparent, which is the default) to 1.