I suspect that the FRoman Catholic issue with Paul is that he contradicts most modern (post-Trent) Roman Catholic teaching.
The last totally Pauline teaching emanating from Rome I am aware of is the Council of Orange.
How do Protestants respond to this quote from Saint Paul? He affirmed the Eucharist in many places in his letters. Yet you reject the Eucharist?
1 Corinthians 11:23-26
New International Version (NIV)
23 For I received from the Lord what I also passed on to you: The Lord Jesus, on the night he was betrayed, took bread, 24 and when he had given thanks, he broke it and said, This is my body, which is for you; do this in remembrance of me. 25 In the same way, after supper he took the cup, saying, This cup is the new covenant in my blood; do this, whenever you drink it, in remembrance of me. 26 For whenever you eat this bread and drink this cup, you proclaim the Lords death until he comes.