My big boy, Monty, often sleeps with only the third lid closed. it doesn't make his eyes dry, but they do tear somewhat, when he wakes, but not to the extent that he gets stained on his face.
A friend , on another forum, has a relative whose black and tan has a large overbite. It causes him no problems, but he is rather a messy eater.
I have two dogs with one testicle (it's usually the right one affected0 not fully decended. I was advised that they can descend as late as 16 months of age, but my boys didn't. If the testicle/s is/are within the body cavity castration is highly recommended as the internal organ can become cancerous. My two have a partly descended testicle, which is not such a risk and two vets said it was ok to leave, provided the odd testicle was monitored. However, the vets, who've taken over the practice, recommend castration anyway.
If a testicle is partly descended, some people reckon that gentle massage can help it on it's way, but it didn't work for mine.
Barbara, Monty, Joly and Teddy.