Hi y'all!
Still trying to solve my problem with no progress, so i'm bugging you lot once again.
First off, to reply to Kyles suggestions; first I created the top-category in Kunena and secondly created the group-categories in GJ. The preferences were set so that registered users can make auto-published groups in the GJ categories. Subsequently I did the GJ fix which created categories (under the top-level) in Kunena. In short: no forums except from top-level were made manually.
Making groups as a registered user (having debug mode active) didn't result in any errors, but the forum tab still didn't show.
BUT, if i choose "edit group" after making the group, the forum-tab suddenly appears. Additionally, if I do not edit the group, I find "Group: missing forum ID" in the tool-page of GJ.
I can of course fix forums from the tools-page but I'd really want them to auto-create and the tab to appear as soon as the group is saved the first time.
Is this at all possible?
Thanks for your efforts (especially Kyle).
/Daniel