Just took the 462 today. 50 questions in 155 minutes. The test center provided dry erase paper. I did not ask about the bathroom break but they did not let me bring a bottle of water into the room. They kept the bottle outside and told me I could go outside to drink from the bottle but I would loose the minutes by doing so.
The 462 TK is NOT enough. You need to read BOL, MSDN. Also followed articles from sites like mssqltips or databasejournal.