I'm going through the Alaska sample data tutorial for QGIS 2.2.0. Some of the lake labels appear and disappear at different scales when zooming. At 1:314,460 Becharof is visible, but Lower Ugashik doesn't appear until 1:157,230. It seems like others have had similar problems.
I have played with the rendering and placement dialogs to no avail. Even if I don't have the "magic combination" of parameters set, shouldn't they all behave the same?
For my needs, this may well render (no pun intended) the program useless. I need it to print labels when I need them!