Benji is the same...we let him out often during the day but put newspaper down in the evening.!
Although he sleeps in our room (I know but only way we could get any sleep!) he goes downstairs to toilet.

He's been with us for 4 weeks now and we're nearly there. All overnight toilets are on the paper and 9 out of 10 times he'll ask to go out during the day!
The only times he does go indoors during the day is when we've taken too long to get him out there!!
But I have to admit that it took us a good 2 weeks to realise his routine and when he needed to go so that may take time.
Re the mouthing, obviously all puppies do this as their teeth are coming through.
We asked about this at puppy training classes and were given advice to introduce bite inhibition.
Basically, he needs to learn what is, and what isn't, acceptable.
So all the time he's gently mouthing we let him carry on and as soon as he goes too far we have to yelp really loud like a hurt puppy would and ignore him for 3 minutes.
He picked this up really quickly (although apparently it can take up to 6 weeks) and never bites too hard now.
Worth a try, it worked for us. But the whole family has to agree on what you will and won't accept.
You can test on each other by pinching hands!!
