Sufski and BJJ in Portugal

Last week I went to a Surfski training seminar on the seaside of Portugal. During the course I met a BJJ black belt, Prof. Joao Luis, who trains at a gym close to where I was staying. He invited me to Academia da Vila.
So after 4 hours of kayaking I have decided to join him and learned new technique. How I can get a side control when my opponent tries to pass my open guard. I also had the chance to roll with a brown belt, who had a talent for being able to submit his opponents with a loop choke from any position.