If you can't find where the obstacle courses are, they're in Full-game Leaderboard.

Unfortunately we have to put it here instead of in Level Leaderboard, so that the times get ranked in ascending order, like in the game.

Just to add - the_androgyne and myself have had several discussions about how to make this work better. I am going to check with the site admins to see if individual levels can have per-level or per-level-set settings like "ascending timer", but otherwise, pretty much every option is going to be some kind of compromise.