PokerTracker

I'm just wondering when i'm observing tables that i'm not sitting at will the hud still appear
the way it does on PK4 pc version?

There is no difference with the Mac version in this regard. The Hud will only appear when hand histories are available for observed hands, which very few sites write these days. In addition, the 'Memory Grabber' option will enable import of up to 30 observed hands from PokerStars.