I'm locally testing phpBB 3.2.0-RC2 and there is still some unresolved permission issues. To reproduce:

• Install a fresh copy of phpBB 3.2.0-RC2.
• Go to the PERMISSIONS tab, click "User permissions" under the "Global permissions" in the left hand pane.
• Click "Find a member" and select your username (or just enter it).
• All permissions should be set to to YES. Click "Advanced permissions" and click the "All No" link
• Submit and then go back. The permissions do not update.

I believe this also happens in Group permissions (clicking "All No" or "All Yes"). I'm unable to test at the moment.