Silverbucket's instructions and documentation has moved to a new address:
There are two different features to set absences for people. People’s holidays are handled with projects which project type is absence. You mark holidays by making resource allocations for people in the “holiday project”. If you need to set long-time absence for people who should also be taken off from the capacity, you can use the admin tool “absences”. As an example, a long-time absence could be maternity or student leave.