digirack limiter and other plugin questions & help

I'm having a hard time using this limiter... it acts more like a compressor than a limiter. Is there something I'm not getting? I want to use it as a hard limiter, is it stuck on soft? also, just some questions about the different icons in various places on protools; What does the Zero with the slash thru it mean on some plugins? I can hear a difference, but I'm not sure what it does. Does it reverse the phase? What is the bull's eye for? thanks. I have some more questions, but I'm not at home, so I will post them later once I look at protools and remember what they are.

....and the 'zero with the slash thru it' indeed is a phase reverse button.

Actually, the bullseye (called a 'target' in PT documentation) is when you already have multiple plugins showing and you want to select one to accept keyboard commands. To do that you click the appropriate plugin 'target'. To open multiple plugins (from the PT documentation): "To open an additional Plug-In window: * In the Mix window, Shift-click the Insert button for the additional plug-in."