Combo Box Blank Title 92301

I didn't post real clearly on my last message. So I will try this again. I am wanting to create 2 combo boxes something similar to what you would find in the Alert Group Maintenance screen. For example, the box on the left would display values from a UD table. The user would select values and hit the right button and it displays those selected values in the right combo box. Then in return it would store in the table I have selected for my source to save the data to.

I am having no luck so far finding some information on how to create something similar to this. Does anyone have any ideas how I could do this or something like what is in the Alert Group Maintenance? I want the user to be able to select available options and move this to the right box to display selected items.