Setup (syslinux/extlinux) on debian jessie as Alternative Bootloader for GRUB

Hi there. Had someone of you the Kung-Fu to tell me how to get Syslinux/Extlinux workin' on Debian Jessie as alternative to GRUB?

I had a follow Setup (VirtualBox):

sda1 bios_grub (always configured on GPT HDDs) without any FS, choosen is bios_grub
sda2 /boot btrfs
sda3 swap
sda4 / btrfs
sda5 /home btrfs

I read already many (solutions; howto's) online with ever the same result after reboot:

Missing OS
FATAL: INT18: BOOT FAILURE

Any ideas?

Regards
nightcrawler

UPDATE_01: Parameters for sgdisk /dev/sda --attributes=1:set:2 were wrong. I had to set them : ...=2:set:2
So now my Extlinux boot, but still every 3 seconds reboot/restart inside my bootmenu

Hmm.... I'am a dumbass... who can read and tap correctly is clear in an advantage...

I was typing the vmlinuz and initrd parameters totaly false, now my debian jessie boots with extlinux.

[SOLVED] so far

Hi, did someone know howto setup subvolumes under btrfs and let the System boot from a subvolume?? For now, i found a solution where i have a Debian 8 with Btrfs Subvolume Snapshot Boot Environment. Here i can create subvolumes and make them bootable in grub. But this is not what i'm searching for. I would like to press the whole "/" to a subvolume and will boot from this subvolume...

regards nightcrawler