I seem to have found one answer to my question. It involves using the plug-in “bbP Private Groups.” However the solution provided by this plug-in is quite complex as it was made primarily for different purposes. But it does let one create a new set of groups, one assigned to each individual member as defined by their forum role (moderator or participant), and one capability setting for a group is to permit those members to publish and edit replies but only to view topics. I would still like to see a more straightforward solution if someone has one. Thanks.
ok. solved. First, a bug: when editing the super-admin in a multisite site instance, there is no field for editing/assigning a forum role. That line is just missing on the Settings->Forums page. Second, I did find a reference to a bug from a year ago that said that one could assign/edit forum roles for individual users but not on the Edit All Users page. That still seems to be the case. And finally I did find the settings entry for assigning all visitors a default forum role. So using all 3 of those considerations, my problem is now solved. (A pain, though, for assigning the super-admin. You have to make the default role what you want his to be, then “visit the site”, then change the default role back to what you want it to be for others.)
Update: It is probably the case that my problem is not with the attachment button per se. I see that I only have it (where I do) because I have a plugin called “GD bbPress Attachments.” But that requires bbPress forum roles and I had not set those up on my new Multisite instances. My problem now is that I can’t figure out how to assign those roles to users. I tried “Change Forum Role to” in editing user roles but it doesn’t take effect. Now where do I find the solution to that problem!!!
