This setting is global for all users!
1. Enter Workcenter "customizing mode"
Add "&sap-config-mode=X" to the end of the workcenter-URL:
Example:
ags_workcenter?sap-client=100&sap-language=DE&sap-config-mode=X
or
ags_workcenter?sap-config-mode=X
2. Right-click on one of the workcenter tab and select "Settings for current Configuration":

3. Click on "Tabstrip Control"

4. Click on "Re-Sort"

5. Define the order of the tabs using the buttons "Up" and "Down"
