Last night, when I got home at about 1 am, I signed up for the two big events at Paizo Con on Friday and Sunday evenings. These two transactions went through smoothly.
Then, I went into the Event Trading area and made two consecutive trades. I had the 60233 Pathfinder Goblins & Dinosaurs event on my schedule, which I traded for 60260 Green Blood on a Black Rock. This transaction went through smoothly. I then traded 60260 Green Blood on a Black Rock for 60292 Midgard Grandmother's Fire, and this change did not show up on my schedule. I then attempted to sign up for 60292 Midgard Grandmother's Fire, which was listing as having an open seat. I was directed to refresh the page, but when I did so, the event did not show up on my schedule. I should have been placed into the 60292 Midgard Grandmother's Fire, since I traded for it and subsequently clicked the sign up button when it was showing as having an open seat.