I've added a new menu item in the CP Admin menu (in cp2_lib around line 1200), but when I click on the option, I get the following error message:
<pre> The page and/or tab you requested is unavailable. The required code could not be properly loaded. Please ensure
that all scripts, libraries, and templates have been properly uploaded.
</pre>

I called the new page 'test' and uploaded cp2_test.pl (a copy of cp2_paths.pl) to my Templates directory. What other changes should I perform in order to display a page?

I've found it: I forgot to add the cp2_page_test procedure. I think I can manage it from here.

P.S. May I make a kind of 'hack' to manage my menu bar? May I distribute it?

Sure, just head over to UBBDev.

You'll probably want to read this article on working with the new control panel as well: http://www.ubbdev.com/ubb/ultimatebb.php/ubb/get_topic/f/8/t/003595

--
Charles Capps
UBB.classic™ Developer
Having problems? Open up a support ticket!

Thanks a lot!