I have questions.

“I am having difficulty with their British accents”
Steady on mate.

“Is this show a warning against AI, or is it trying to make us sympathetic to the Synths? If so, they're making it difficult for me, since Synths have killed at least three people since I started watching. Niska killed one, and Hester killed two, and lied about it.”
It’s a bit of both.

“They also lie and attack without warning. You can never tell what they're thinking or what they're about to do. They seem very dangerous to me. Stephen Hawking has warned that AI is one of the greatest dangers facing mankind.”
Skynet anyone?

“Why are Laura and Joe so sympathetic to Synths?”
It’s asking us to think about at what point to objects become sentient.


“Why is Leo helping them?”
You’ll find out.

“Why is Sophie exhibiting Synth behavior? And why did her father think he could correct that behavior by having a food fight?”
She’s going through a phase and misses Mia. Dad was trying to bring some good old fashioned (human) fun into the mix.

“Why did Ed and his buddy let Mia go free after she attacked him? And why did the (I assume) government agents refuse to take her off his hands? Didn't they realize she could be faking?”
I guess they were hoping to make a fast buck without any hassle and realised that they’d bitten off more than they could chew. At that point! To have a synth faking a lack of consciousness would have been unheard of.

“How can humans and Synths have sex, and why would they want to? This is very creepy to me.”
Synths were built with an ‘Adult package’ and could also be modified on the black market to become sexbots. Creepy? Maybe, but it would definitely happen in the real world.

“Pete appears to be living with a Synth as his mate. What's up with that?”
You’ll find out.

“Why is Dr. Morrow's boss trying to make Synths conscious, and why does he want to produce Synth children?”
You’ll find out.

I recommend that you watch it from the beginning.