no no ssg peaceful is a different category, it has a different leaderboard than ssg, so you cant.. you can only use easy/normal/hard

The run? any difficulty except peaceful (considering you're not doing ssg peaceful) works

Just stand at the correct spot, crouching doesnt matter but can help you adjust yourself better at the portal. If you still have problems, note the blind cords to the decimals and try to be as close to them as you can.