After implenentation to make redirect to the Tab (Step), scriptwriter should set ScriptContext.Result and ScriptContext.ResultType like in the example below.

var itemFieldTab = Factory.Instance.ItemFields.Read(item.ItemId/*205962*/, itemFieldId /* "CF" + 971*/); // itemFieldId is the Id of the tab on which we want to navigate
ScriptContext.Result =  new TenForce.Execution.Scripting.ResultSet.NavigationResult(NavigationDestination.ItemTab,  itemFieldTab/*"Aankomst werf"*/);
            ScriptContext.ResultType = ScriptResultType.Navigation;