What's an effective way of getting "Pup" to calm down? Right now I've got him in his crate, with the crate covered to block out light, and the crate has a couple of stuffed animals as well as a few beloved chew toys (and of course the lining of a towel and old sweater of mine).
He periodically whimpers at the door, but he's already done his main pee for the night. He had a couple sips of water, and that's all. Should I leave the room?
Also, we have hardwood floors and he's been making use of them. It's beginning to smell a bit like pee in here, despite prompt cleaning of accident sites by drying then swiping with a peroxide-laden paper towel. We have Murphy's Oil Soap, but I'm concerned about residue on his paws. Any suggestions for a decent cleaner?
I would ignore the whimpering otherwise you're reinforcing that whimpering = getting attention. As for the pee cleaner I am not sure, Milly never really pee'd inside the house so we never needed anything (she has pee'd inside twice in 5 months and both were in her first month that we had her) but someone else will be able to help you with that I'm sure!
Dogs/puppies are very sociable animals and want to be cuddled next to someone when they're resting, sleeping. So that transition from always being with and next to their littermates to suddenly being orphaned is a tough transition for any pup to make.
Some playing, chasing a ball, to wind down the pup's rubber band motor before bed time may help. (But if it only winds it tighter, then that's not a good idea.) Having a radio playing soft music or voices talking at a low level may also help in addition to the covering the crate. And time (like in several days or weeks to adjust to the big transition).
Re: the peeing: Is there an area at home without wood floors? Like a kitchen with linoleum? I puppygated Puff to such an area until she was house trained. That made cleaning up and training much easier. The hydrogen peroxide you're using is a wise decision -- it eliminates the call of the pee-spot to pee near it again. A commercial product, "Nature's Miracle" is also used by many.
Also, you might read my post in this thread about how I house trained Puff. Possibly it would be useful in your situation.
You didn't ask but, as far as the food for your pup, many of us would recommend a large breed puppy food, such as those made by Diamond, Eukanuba/Iams, Nutro, ProPlan, Science Diet, etc. While the Lab standard describes Labs as a "medium size dog", the long term scientific nutritional studies on canines usually define a large breed dog as having an adult weight over 25 kg (55 lbs.). So, regardless of what you call them, those studies apply to dogs in the adult weight range of Labs.
In these, long term developmental studies by many researchers have shown that specific low levels of calcium and phosphorus during the first year are critical for reducing the incidence of later joint problems in large breed dogs.
Puff [YF, AKC field line (from competing HT/FT breeder) 62 lbs, dob: 8-'01]