You can backup your Image via telnet (commands are in ' ' )

BACKUP
1. 'cat /proc/mtd' to locate the flashimage...yes it's mtd7
2. 'cat /dev/mtd/7 > /tmp/backup.img' now you can transfer the backup via ftp to your PC or whatever
3. execute mkdnimg-1.0-win32.exe and create image installable with Flashtools_Installer for your type of receiver

RESTORE
1. to flash it back copy backup.img to /tmp
2. 'cp /bin/busybox /tmp' then 'cd /tmp'
3. 'eraseall /dev/mtd7' wait for prompt
4. './busybox cat backup.img > /dev/mtd/7' wait for prompt
5. 'reboot'
6. you're done