Advanced editor lagging after last update

Ever since 3.55b112308, whenever I'm in the editor, it laggs really bad. Selecting an item, changing between items, layer etc or even just ticking the box at the end of an item row freezes everything for 2-3 seconds and no I do not have the pause animations button on. Sometimes the app will kick me out and I'll get the notice "KLWP keeps stopping - wait - close app - report". On screen, everything works fine