Could you help me find out why BackupMenu does not mount the partitions of the phone as r/w. They are just readable. Is there specific keys/commands to enter in case to make it?

Edit 1 (few hour later)
Finally I did it. Now there is 4th partition mmcblk0p4 (ext3 type) over 4G. All files from the image debian-m5-v3e-Sci-2GB.img.ext2 are copied. All made trough Ubuntu
... And after restart the phone is still working
But the partition mmcblk0p4 is not permanent mounted. After the reboot it is missing. Probably I need to add permanent mount.
Then will read further how to edit the .chroot and to bring the icons up in the menu.