Thanks. By the way, it does have 210 rounds through it and it runs perfect. Also, I am absolutely positive that I properly seated the RSA before the putting the slide back on (unlike my previous thread where I started to have doubts, but now believe that I properly seated it that time as well). I am not new to Glocks, and am in the habit of properly seating the RSA.
I did get the slide off by re-seating the RSA (not an easy task).