Hi omar_tx, first of all you need to set a new Audit query (as there is no one by default created)
You just need to go to Menu->Reporting->Queries&Reports and create a new query (Logging->Audit Log Entries) selecting Table as display results. You can filter anything you need or show everything.
Once your query has been created then you just have to set a new Server Task (Menu->Autmation->Server Tasks) that will run the previuosly created query and export it or send it by mail as sub-action and schedule it at every week
Thank you! This worked just fine.