The bible uses saved and born again interchangeably. It is when you believe in Jesus and receive the indwelling of the Holy Spirit. No, RC's are not automatically excluded and it is something that can never be known about another person.
How specifically do you see Catholics rejecting Christ's act of Salvation?
By never making it clear to an RC that he is saved when he is born again. RC's never know they are saved and are never sure they are going to Heaven. OK, every once in a while I find one that is but in general they are not and use such terms as "the sin of presumptiousness" on me for knowing that I am saved right now.
Neither did St. Paul. See post # 111 above.
Have you ever actually been to a Roman Catholic mass? And if so, which specific portion of the mass was inconsistent with what is in the Bible?