Well you certainly don’t get to try again, as I found out. I was in Miami on the way back from Panama, chatting with some new travel hacking friends I met on the flight back. We headed over to scan our documents at the Global Entry kiosks. I was going through the standard answer the questions, take a picture, scan your fingerprints, and got the last screen, where it said “Validating information. Times out in 31 seconds”