Adding LE to a Linux is fairly easy (if you know what you're doing...). No idea how the approach works on UEFI hardware.
See this link and please report back if it works.
Thx for your help! I'll try and report!
Just that I understood:
- In the 1GB ext4 partition I just copie the system and kernel file
- Then I have to configure manuelly the grub2 entry for LE.
Perhaps you can explain the lines I have to add in 40_custom to boot into LE(I think there have to be the UUID of the kernel or system)