[Typo3] one-time displayed popup

[Daniel]

also, my problem is in the typoscript setup code. i can display a
popup window with the gsipopup extension, but only if I create a page
outside the main page tree (and I think it is beacause the global
typoscript code).

I have tried to remove certain code blocks from the code but the did
not appaer. It is very strange, on the other page all works fine.

does anyone know if the extension need something particular setting?

thanks in advance,
daniel