Answer to "iPhone 6s keeps lagging and freezing"Try resetting your iPhone. It must help.
Answer to "runs for about 15 minutes then stalls?"I think there might be multiple problems, but mostly it should just be timing or some issues with the computer, because i have a skoda superb that had it’s computer replaced because of a similar problem, or you can also try to check your wiring
Answer to "Keyboard keys S to L not working"Hi, even i have the same model of the MacBook Pro, and this keyboard damage might be because of water, or internal defects, try replacing the keyboard
Answer to "Glue for lcd repairing"Yes, of-course. I have been using glue for quite some time now and it works really well, but try to use it as less as you can with LCD displays, as they are often easy to break