Reiko,
There is no way to do this in configuration.
I have far off "to do" plans of adding a radio function, but it will require several lines of code change.
Well, yes, maybe only one, but, I want the frame to close if not a radio (save memory), or hide if a radio page.
If you (or anyone else for that matter) knows GLua (The Gmod functions of Lua) and want to tinker, look into Umotd_client.lua.
The button is now set to :Close()
I'm pretty sure that would need to change to :SetVisible( false )
Problem is, I've looked around the GMod Lua Wiki. Panel has a SetVisible. The DFrame I'm using doesn't show one in the Wiki.