Sorry, I couldn't think of anything else at the time
I just remembered another - if you think you're walking on a red/different coloured footpath, you're wrong (it's more of a city thing if I recall correctly). They're actually designated bicycle tracks so try not to get in anyone's way. Being Australian I always tried doing that by moving to the left while the Germans tried to avoid me by riding on the right...that usually ended with me just running the hell away to avoid a collision
I couldn't tell you about the j-walking thing. In my experience, the police working in Wacken are essentially there to make sure everyone is having a good time, and they're the only one's I've ever seen anywhere who actually enjoy their work. Last year on my way to Cologne there was a train on the other track full of football fans...there were about five police to every train door, complete with riot gear and police dogs. When Quark and I got off the train at Itzehoe for Wacken, there were two police in high visibility vests, smiling, saying "viel spaß" (have fun) to everyone