I will have a look on it on monday. I will start over with a fresh mind. When everything will be easier why should I try to get it working this weekend. Thanks for the hint!
I know the idea of integrate. When I check the documentation on the BBpress site about integrate I find this:
“If you would like to pull user information from a different database, define USER_BBDB_NAME, USER_BBDB_USER, USER_BBDB_PASSWORD, and USER_BBDB_HOST.”
Now I don’t how to do this. I should add this to the config.php file, but how and where exactly to put this is not clear to me. A visitor doesn’t seem any difference and I will not have big MySQL databases.
When I find out in a later stage that I have a lack of visitors I can remove all the data within an eye wink instead of the big adventure of finding everything concerning BBpress in the WordPress database.