Hi and welcome to YT
!! CONGRATS on your new baby, he sounds so precious!
For the barking....this is a tough one, bc it may just take a good amount of time, to be honest. You may want to buy the Bark Genie -- and stand outside the door when you leave, and then each time he barks, try the Bark Genie...this may help...? Some people here have had very good luck w/ it.
For the neighbor...since she just shouts over you and doesn't listen, what about writing her a little letter, explaining what's going on and what you're trying to do about it...and letting her know that you totally understand her frustration...give her some validation.
For the running off, that's another tough one. NONE of my dogs will stay right by us if we're out and they see a dog -- so they are never, ever off leash. Some dogs just will not stick around if they see another dog.