The changes you make to the Default layout are available only to you. If you need to make these changes available to all WorkSpace users you need to export it and configure WorkSpace to use the exported layout.
When you export the Default layout it is stored in an XML file. You must not modify this file manually. If you need to make changes, make them in the WorkSpace and export the Default layout again.
For more information on how to export WorkSpace Default layout, see Exporting Oracle BPM WorkSpace Default Layout.
For more information on how to import a customized Default layout, see Importing Oracle BPM WorksSpace Default Layout.