I'm not sure what kind of answers you are expecting, because noone here knows your game and/or anything about how you have your events set up..
You might just be looking for a magic button within crosswalk export, but if there is I haven't found it yet..
Optimizing would consist of going over your events to see if there are many every tick events (all events without a green arrow) that don't need to be checked every tick..
see how many collisionchecks there are every second (open up the debugger for this one)
See if you are using delta time (dt) the right way to make your game framerate independant..
You could also just look at the debugger to see what is taking the most amount of processing to see where the framedrops come from..