Alexander Wechsler (MVP for Windows Embedded) has been working on a utility to make it easier to build Windows XP Embedded systems that use EWF (the Enhanced Write Filter) and HORM (Hibernate Once, Resume Many) - The utility is called HORM Manager Pro for Windows XP Embedded - I know from experience that working with EWF and HORM can be tricky - so this utility looks like it could be a great tool to add to your Windows XP Embedded toolkit.