Hi Radeonized,
Unfortunately, there is no easy way to do this at the moment. Since the dirve indexes could change between Winodws and DOS, Ghost try to access the image while in Windows and create an identification using many parameters. Currently, only way to access the image is either using drive letter or the volume label - but both of them are not available in a hidden partition.
One alternative is to store the image in the Windows partition instead of the hidden parition. You may be aware that Ghost can clone partition or a disk using an image stored in the same partition or the disk (feature is called client staging area). If the image is protected using NTFS permissions, unauthorized accesses could be blocked.
Other option is to keep the image in hidden partition, but running Ghost using the command execution. This is easier if you do not need to do configurations after cloning the disk. If the image is unique to the machine, there is no issue of having the same computer name. Even configurations could be applied by running ghconfig after cloning, but it is bit of work. If you would like to investigate this and need more info, please let us know.
Krish