From time to time there's a couple of levels that don't have comments enabled, and it's always a pity if nobody can comment on them and give them some helpful critique.
Always try enabling comments, please. It's not set this way by default due to some coding difficulties (as I heard) and if it doesn't work on the first attempt, keep trying. Since enabling comments does "nothing" but creating an automated topic in this subforum, you can also try creating a topic manually if you have a technical problem.
If you're afraid of getting criticism, there's no reason to be - you should be able to accept constructive criticism since it's only for your benefit, and should there be an offensive comment or any other comment that doesn't comply with the rules, you can always use the report button.