"...we have decided to let those members participate in the frag swap after the 3rd round."I think this sums it up. You need at least 3 corals to participate from the beginning. 3 standard corals (that aren't on the ban list) get you in, 3 bonus corals gets you in and a bonus ticket. 3 ultra corals would get you in and 3 bonus tickets.
No corals and you can start picking on the third regular round (I think).