I forgot to mention this if it makes a difference- we are flying form Edinburgh this morning to LHR on BMI which is a *A member. Two questions then-

Can I use a *A lounge with the BMI ticket AFTER we land?

Will BMI check our bags all the way to EWR, so we don't need to go outside, get them, then go back through security? We'd like to go into London for lunch time permitting and this would help greatly as I have a 4.5 hour lay over...