Hello Klaus
Thanks for your attention.
I did the customizing on ATC transaction, and now it seems I'm able to create exemptions.
About the possibility you mentioned, please let me confirm if I got it right:
Since ATC is client independent, it might be possible that some developers apply and approve their own exemptions.
It would only be possible if they include their usernames in the customizing "Exemptions -> Maintain Approvers" in ATC transaction, right?
Regards
Daniel