Arena Jashan

I'm on a Macbook Pro Retina 2012 I tried this new build of Kokua - was trying not to crash at the 'new stuff' opening at Kustom9 store where a lot of people are at - using the official SL viewer I crash after about 2 min. just being near the store - with Kokua I can get close to the store, zoom in with my viewer and browse inside for about 10 min. and then I crash. I find it a bit silly that I can't be in a crowd - that sl is that much weaker on a mac - why is it ?!?! I have my draw distance set to the lowest possible setting but I've tried messing about with the graphic settings and that doesn't seem to change the fact that if I'm around 8 people or more I have to keep my view focused on the grass or a wall so I don't crash in the first 20 minutes. But if I'm with one person at Botanical gardens I can be on sl for as long as I like ?!?!