You gotten a lot of good advice so far.
Welcome to being owned by a yorkie! lol.
Seriously, yes, too much freedom on the potty training. And you need to tell your bf that he needs to keep up with it! NO variations because this will only cause the chaos it has. Unfortunately, sounds like you will have to start all over with the crating, expen or gated area.
As for standing there when they are eating, well good luck. Mine are 2 and 1 1/2 and they will do that as well. I am actually able to go back to cooking sometimes while they eat.
People food-I am bad at that. they each get a bite of something so long as they are in the beds while we eat dinner. If they roam or don't come over during dinner, they don't get anything. What ever we have, I try to give them the least fatty. Usually they get a bite of veggie or potatoes.
as for treating while doing tricks, try to quickly say 2 commands in a row before treating. Like, say "sit" and at the same time, motion and say "down". Don't give a treat until she does it. you may have to repeat it several times but try it. as she gets older and understands more, it will get easier. from time to time, just give praise for something well done and increase that praise. before you know it, you'll cut the treats way back.
Good luck!