OK, although the problem is marked as "Solved" it is not.
DISCLAIMER!
I'm a Linux user and tested this solution only with Linux. It has very big chance to work with Windows, but I cannot tell, if this would work without extra effort.I've created a "prosthetic" bypass allowing me to avoid Lenovo service and (most probably) very expensive option of replacing MB.
To the point.
Premises.
I had working Antergos installation while discovered the BIOS issue. Wanted to install new system but was not allowed to change boot settings (nor in BIOS or via boot menu).
Using command:
efibootmgr -v
I've got my EFI boot configuration that looks like this:
BootCurrent: 0001
Timeout: 0 seconds
BootOrder: 0001,0002,2001,2002,2003
Boot0001* antergos_grub HD(1,GPT,f128f12b-fa3e-45b1-b5c9-f03c328498cb,0x800,0x64000)/File(\EFI\antergos_grub\grubx64.efi)
Boot0002* Windows Boot Manager HD(1,GPT,f128f12b-fa3e-45b1-b5c9-f03c328498cb,0x800,0x64000)/File(\EFI\Microsoft\Boot\bootmgfw.efi)RC
Boot2001* EFI USB Device RC
Boot2002* EFI DVD/CDROM RC
Boot2003* EFI Network RC
It means the file grubx64.efi in antergos_grub directory will be loaded as first. Nothing else. And from no other drive but the 1st having the ID: f128f12b-fa3e-45b1-b5c9-f03c328498cb
So. Am I forever bound the Antergos? Well, no.
Long story short.
I've downloaded rEFInd package and REPLACED the antergos_grub directory with the content of rEFInd package, renaming the refind_x64.efi to grubx64.efi
Now, after restart I've rEFInd boot menu (you can compare it to the BIOS boot menu) with the option for selecting boot source (including USB drives and optical drive (my case also via USB)).
This way I was able to install openSUSE and few other systems in between.
BUT!!!!
You must never erase the first partition with the rEFInd bootloader.
It will bind automatically systems installed on the next boot partition.
What if my hard drive got damaged or anything... Well, I thought of that too.
Using command:
sfdisk -d /dev/sda > HD_partitions.txt
you get a file named HD_partitions.txt containing IDs of all your partitions.
You only need the first value. In my case:
/dev/sda1 : start= 2048, size= 409600, type=C12A7328-F81F-11D2-BA4B-00A0C93EC93B, uuid=F128F12B-FA3E-45B1-B5C9-F03C328498CB, name="EFI System Partition"
I took second disc, made same first partition on it, exported the partition table with the same command and REPLACED the uuid value from the main disc.
Then what you need to do is flipping the "pipe" direction, from ">" to "<" and write the partition table to another disc:
sfdisk -d /dev/sdb < modified_partition_table.txt
(Assuming the second drive is sdb!!!).
That is all.
TL;DR
rEFInd is your friend.
Thank you for your attention.