Never had any issues with passport control, security, etc at CDG. The closest thing I had to a horror story was almost missing my flight home (CDG-ORD). I left the hotel 2 1/2 hours before my flight. Thought that would give me plenty of time. Of course, I get stuck on the A1 for almost 2 hours due to a fatal accident. I made it to the UA counter just as they were closing up shop, but convinced them to check me in. They had a little sympathy for me as there had been people trickling in for the last half hour, also having been stuck on the A1. Made it to the gate just after they had started boarding seating area 1.