DPanel inside DFrame

[Axspeo]

Hey guys,
Is this the correct way to make a section of a DFrame and Fill it with a Button.OnClick?

    Menu = vgui.Create("DFrame")
    Menu:SetSize(1000, 600)
    Menu:Center()
    Menu:SetVisible(true)
    Menu:SetTitle("Menu Example")
    Menu:MakePopup()
    function Menu.Paint(self, w, h)        
        draw.RoundedBox(0, 0, 0, w, h, Color(255, 255, 255, 255))
    end

    local d = vgui.Create("DPanel", Menu)
    d:SetSize(970, 610)
    d:SetPos((ScrW()/2)+250-500, (ScrH()/2)+110-300)
    d:MakePopup()
    function d.Paint(self, w, h)
        draw.RoundedBox(0, 0, 0, w, h, Color(200, 200, 200, 200))
    end

// Section
 local Content = vgui.Create("DExample1", d)
  Content:Dock(FILL)
  Content:SetVisible(false)

    ... CODE ...

// Make Section visible with a Button.OnClick
    Content:SetVisible(true)

I'm having a problem with this code, if I make 'Content' (DExample1) visible the moment I create it, it works. But if I set it's visibility to 'false' and then use the button to change it's visibility to 'true' I can't click on it's CheckBoxes and etc...

Already tried to set it's zIndex to the highest with Panel:SetZPos(index) but it doesn't seem to work.

[FireWolf]

Could you not just put the content code in the button.DoClick function so that when you click the button it creates the code.

[Axspeo]

I could do that but it doesn't fix my problem.
Tried changing zIndex to 32767 (max = 2^15-1) and still can't click it.