I wanted to update the backupmenu-multiboot to latest 1.2 version from current .65
so I thought the procedure is to extract the files from the new deb file and paste it in the older deb file.
I decompressed the new 1.2 deb file, found /usr/share/backupmenu folder, took it and paste it in rootfs
the exact command I used is,
mv /usr/share/backupmenu /usr/share/backupmenu_old
mv /home/user/MyDocs/app/backupmenu_1.2.0-2_all/usr/share/backupmenu /usr/share/backupmenu

now I can't access backupmenu.

thank you, but I don't think that is related to my issue. Please correct me if I'm wrong.
Can you please tell me the correct procedure?
Also, should I switch to uboot instead? What is your opinion? I'm new to maemo, I'm learning things.
I need a shell access incase it doesn't boot. (And that happens a lot for me)
rescueOS is good but that needs a pc around. That's the problem.