I can confirm, that it works ... at least in my Lua scripted Wizard:
found on page 3 message #27
As I learn more about Lua coding, I like to go back every so often and reread old threads to see what others know and share.
Did not follow just what was going on here at the time, as it did not seem to make sense how to get his code to work or just what he was trying to show. now with time and more understanding I did get this to work. Had to add the call to main() and mainframe:Show(true)
But when you close the popup window it places the text in the windows clipboard. So if you use paste too, in a text editor you will see the message.
Thanks Paul --these are the guys that are in the background doing things the rest of us struggle with.

function onCloseEventOccurred(event)
--exit frame, if it exists
if mainframe then
mainframe:Destroy()
mainframe = nil
end
local clipBoard = wx.wxClipboard.Get()
if clipBoard and clipBoard:Open() then
clipBoard:SetData(wx.wxTextDataObject('hello world\nI was copied to the clip board\n'))
clipBoard:Flush()
clipBoard:Close()
end
end
function main()
mainframe = wx.wxFrame(wx.NULL, -- no parent
wx.wxID_ANY, -- whatever for wxWindow ID
"Example",-- frame caption
wx.wxDefaultPosition,-- place the frame in default position
wx.wxSize(400, 200), -- Window popup screen size
wx.wxDEFAULT_FRAME_STYLE) -- use default frame styles
mainframe:Connect(wx.wxEVT_CLOSE_WINDOW,onCloseEventOccurred)
end
main() -- you have to call the function
mainframe:Show(true) -- then you have to show it
You would paste this in the mcLuaEditor save it to your wizard folder run it and then when you close it your message is available.