I believe since I upgraded to Joomla 1.5.10 when I try to add a new Field in Field Management my admin goes to a blank screen. Also, when I click the pagnation from 20 to 50 or ALL - also goes blank.
However, when I click ADD NEW in Tab Management it works fine.
They both seem to connect to index2.php ... but one goes blank.
As is stated on the release announcement of CB 1.2, it is highly recommended you use at least PHP 5.2.3, but preferably the newest version. Your version is old. Also see the FAQ regarding blank pages.