It looks pretty healthy overall now, so I wouldn't worry about a few lower leaves getting crispy. If it seems to be spreading up the plant, or if the plant starts showing other signs of being sick, maybe worry then.
You have a very indica-looking plant, and that might account for the slow growth in flowering. Short and stout, but with a nice thick central cola, that's what you should be hoping for.
Keep the updates coming, I'm interested to see how this turns out for you.