DOOR UPDATE!

Ok so the door got installed yesterday. I'm still in shock!

Apparently I did need a 79 1/4 inch door as the door they sent was a
little more that a =BC inch short. They installer centered it and put a
rubber flap on the bottom to prevent any air from getting in. He said
this is common and not to be concerned. My question is, should I be?
I do not feel any air through it nor do I see any light pass through it
when using a flashlight.

Also the door seems very tight, knob is a bit hard to turn when
opening. It not hitting just closing tight! He said this would break
in and loosen up. Is this common?

Felix