So I tried a couple things here.
1. I changed the action from left-clicking the checkmark to "Every 1.0 seconds" to set the global variable (juiceprod) using the selected text on the dropdown and
2. Created an instance variable on the dropdown box and have it set every 1.0 seconds to what the selected text is showing
This showed the dropdown instance variable being set as I selected different text but the global variable wouldn't set. The juiceprod is set as a string - global variable so I'll do some more testing.