Trying to moderate and change a comments status (Review to Members) from 'collections' / 'comments' / 'full text view' results in a BAD REQUEST error. Status does not change. Using the Button! One has to Edit the comment to change the status.
I found this on my site but also on the b2evolution demo site.
Are you running b2evo 6.8.7? This is fixed in 6.8.8.
6.8.8 should be released tomorrow.
The demo site was just upgraded to 6.8.8 -- you can check.