I need to reuse a complete working solution, with specific set of users, relevant permissions on folder/files, a gigantic set of binary files sparse on two partitions, ecc. So the reason why I need to start from a disk image and just "inject" the minimum set of drivers/patched system files to have XP booting again.
The good thing is that I know for sure that a clean install of XP IE, with options 1,3 and 4, works! So I have to understand how to "capture" the added files and registry settings and restore them, while offline, on restored disk image.