NXT crashing on Mac consistently during Ritual of the Mahjarrat

Its the same part every time. Trying to run across the jungle and avoid the fire balls - I've now lagged out five times consistently and had to force quit.

El Capitan - blah blah everything's up to date. Graphics on minimun only other program open is chrome.

Submitted a bug but this seemed bigger/different than just regular crashing because I cant get past the beginning of the quest. I know Jagex is doing their best to work on these problems but I thought I'd mention it. It has been getting smoother overall.