FIXED THE FIRST RESPONDER ISSUE - VICTORY!!!!

After snooping around the source code of the Secrets preference pane (http://secrets.blacktree.com), I found the way they set the First Responder to their own text box, and applied it to my pref pane.

[self.mainView.window performSelector:@selector(makeFirstResponder:)
                           withObject:self.keyboardView
                           afterDelay:0.0];

I don’t know WHY it works, but it does :D
Added read functionality that populates the popup with plist content for that character.