Affinity Photo 1.3.4 consistently freezes on me when choosing between multiple tools in El Capitan Public Beta 3 and Public Beta 4. I have to force quit the application each time. It's likely an Apple issue, and I've reported it to them, but I thought I'd post it here too. I didn't really start using Affinity Photo until I upgraded to the El Capitan beta, so I don't know if the issue also occurs in Yosemite. I have a 13-inch MacBook Pro (early 2011) with 756GB SSD and 16GB RAM, connected to a 27-inch Cinema Display.