Submitting a large number of rejects would cause a temp-ban. it happened to me a few days ago when I was testing this all out. You might have to wait about an hour before it will let you connect again
sure, but I haven't submitted anything. I haven't even switched to the X11/X13 port... It was just in the list of pools, but the only pool I used before it went dead was port 3333 (scrypt)...