I did it without buttons. If the tect field (perhaps the movie plot) is too long, then I have it set so when you click on the plot, it moves to the next block of text (but still on the same screen). From memory, I think this is how I did it:
1) Open Skin Editor (Pause/Break)
2) Create a text field on a screen (screen tab, enter "category>yourcategory>plot").. use your actual category and item you are going to print
3) On the "Default" tab, name the text box in the ID field (perhaps call it "Plot_Id") (make sure the "text" item is highlighted
4) Close the Skin Editor
5) Create a new event (F2)
6) Make the event call the Xlobby command BUTTON NEXT PAGE, filling in the name of your button from #3
7) Close the event editor
Open the Skin Editor
9) Go to the screen with your text block on it
10) Select your text block
11) Select Item Tab, Then Event Tab
12) Under Click Event, push Assign... then select the event you created in Step 6
That should do it. Now if a plot comes up that is too long for the text box, XLobby will diaplay it with some "..." at the end. Click on the text box, and it will go to the next page. It will only scroll forward, then start at beginning.
You couls do this in a similar fashon, using buttons for (forward and backward), etc