Ok... so...

Basically I am posting on here, because the home office website is as useless as ever...

My situation:

I am an American. I moved to the UK five years ago to study. I got my degree after three years, and got a Post Study visa for two years. My employer wouldn't sponsor me (due to all the government changes). So my immigration options were limited. Luckily, my parents are Polish so I've decided to get a lawyer in Poland to get me my Polish citizenship as soon as possible. I'm expected to get this within three months. I am back in the US while this is going on (I left before my visa expired).

I guess my main questions are, when coming into the UK under my Polish citizenship is there anything I need to provide them with (information/documents)? I really want to avoid having a hard time with border control. When I get back in, I'm looking to get a job immediately, I have friends to stay with, it's just starting fresh, yknow?

I know I need to register under the workers migrant scheme. Is there anything else to do? Can I also use the same information as I was using when working under my student visa/post study visa... such as national insurance number, etc. Will all my NHS information stay the same?

This mess is so complicated an I know the home office can't be there to hold people's hands, but the communication is awful. I remember once asking an officer at border patrol a simple question and she wouldn't even answer my question but told me to look at the website. It was completely pointless. I know I have to sort my own immigration status, but I want to do it correctly... it's as if they're looking for you to mess up so they have a reason to call you out and never let you back it. and it pisses me off cause I paid so much money for tuition fees!!! (I know it's unrelated --- but still...)

So... any advice? Any good websites to look at (besides home office)?

I'm just terrified of strolling back into the UK as a Polish Citizen and them being like, actually no... you're not allowed to live/work here.