Follow along with the video below to see how to install our site as a web app on your home screen.
Note: this_feature_currently_requires_accessing_site_using_safari
Have you got commentary on? I believe that turns cheats on when you activate it so try turning it off and see what happens.
If you go on the commentary in the normal game, and then load up a bonus or advanced challenge, the commentary nodes will remain - thus 'CHEAT', because you're invincible.
It's annoying, but you just have to start up a normal 'new game' and THEN load up the challenge to get the game off 'commentary mode'.
Otherwise, the only reason I can think of is that you had sv_cheats set at 1.