your character has nested masking - both head and the outer bone layer (layer12) are set up to be masking groups. As jahnocli says, you do need to render to see the results in these "complex" masking situations (yeah - it's a pain!). Selgin's pirate just has simple masking -- if you turn off GROUP masking in your head and layer12 groups the viewport shows you what you're expecting (and that's what the pirate has). I haven't looked into why you want masking at all 3 levels - but if you don't need it...