[Traek]

I’m not sure, but is this what you mean: https://codex.buddypress.org/getting-started/installing-group-and-sitewide-forums/

It sounds like you have both bbPress installed (maybe as a WP plugin?) as well as buddyPress Discussion Forums enabled (which are a watered-down version of bbPress). Any insight on your ‘custom install’ would be quite helpful.

[Traek]

What version of buddyPress are you using?

[Traek]

I have a solution that this lovely bbPress installation is detecting a problem with (`It looks like you’ve already said that!`). Gee thanks.

In any case, I created a quick hack that should do the trick for you. You can download the file here: http://www.ungatech.com/download/bp-custom.php. Once you have it, place it in your `wp-content/plugins` directory and it should change the order for you. Let me know if that does the trick or not. I tested it on one of my sites and it seems to work okay.

[Traek]

If it helps at all, I just went through registration (using Chrome 21.0.1180.83 m) without any issue. I got the confirmation email which linked back fine and lets me in to the site without problems. My new user is bptester for proof

[Traek]

I just got done doing this last night with one of my sites. It was PAINFUL because I created a few users first before doing the import. This unfortunately led to me having to renumber a LOT of records that linked posts (including activity) to individual users. For what it’s worth, here are the tables that I moved using phpMyAdmin that seemed to get everything I was looking for:

Assuming a prefix of wp_ for your database (mine was not and yours shouldn’t be either so change as necessary):

wp_commentmeta
wp_comments
wp_bp* (everything here was critical for activities, existing friendships, etc.)
wp_usermeta (this was critical to get the users to show up in the members list)
wp_users (duh)

The big question is why did you want to not bring the users over? Everything you mention initially is tied to a user: activity, forum posts (unless you just want the empty forums themselves, that’s easy) and even groups (someone had to create them). What are you really trying to accomplish and maybe we can help with a little better understanding