Single player custom maps issue

[kkfnx]

hello,I'm new at portal 2 and i would like some help with a problem that came up.
I downloaded few custom maps for single player from workshop but i cant play all the map after i finish the first test the map ends and ask for my rate.
any ideas?

[Berti]

That's how it works, actually.
If you finish the last chamber on your queue, you need to go back to the chamber list, subscribe to another chamber and play it when the download is complete. If you have downloaded another chamber in the queue after completing the current one, there will be a button to go to the next chamber.

[kkfnx]

Lets say i try to play 12 angry tests part 1
i get the ending screen[i.imgur.com] after 20sec of game when i pass threw the 2nd door and get at the elevator,and there isnt a button for the next chamber.

[Berti]

Ok, so after you complete this chamber and you go back to the list, is this the last one? Are there any other (under) downloaded chambers?