The error "Unable to control A20 line" leads me to point you at this thread:
https://www-secure.symantec.com/connect/forums/could-not-allocate-page-table-memory-1
Read the post by Nigel Bree, one of the former Ghost developers. There is a link to an alternative version of himem.sys which you should try in your DOS boot image.
Incidentally, you cannot use any USB device for logging Ghost errors on the A: drive - it can only be a USB floppy drive, as this is correctly identified as a floppy by the system bios and mounted as drive A. USB flash drives and hard disks have different descriptors in the information string they return and so are treated differently. Since DOS has no USB support, you have to rely on the limited bios support here.
Ghost 11 does not come with WinPE as an alternative to DOS integrated into the Ghost Boot Wizard. The other issue with DOS is no SATA support, although many bioses still provide a compatibility mode to emulate the older PATA (IDE) interface for hard disks. Nevertheless, the CHS addressing system used by DOS does not support really large hard disks for which true LBA support is required.
Sooner or later you will need to move to WinPE to fully support modern hardware, but hopefully an update of your DOS extended memory manager as detailed above, will give you a solution for your current issue. This should also continue to work with your other models.