...

Yes it is, technically, with a caveat.

Practically the devs added an absolutely artificial block (if sees 7, make up a fake error), the game runs on 8.1 but 7. The fix the above person mentioned is kind of shady in my opinion and only for Steam and includes a foreign EXE, I strongly discourage for compatibility/security reasons. Many games, like new "Myst" or "Serious Sam 4" run fine on 7, this move is truly unfriendly, it must be undone.

How can one undo the unjust on a GOG copy in a HEX editior to make it run? Not Steam.

Remember: you are doing this on your own risk!

Instructions for build 49215 are in the post from liara42 (see below)

GOG build: 46815
FIle: Little Nightmares II.exe
CRC (before modification): 150BF553h
Offset: 051FBB1h
Replace: 75h with EBh
CRC (after modification): 3CD3BB97h

This will bypass that artificial version check and will allow to run the game on any Windows version since (and including) Vista.

Enjoy.

--- Update ---
Fixed erroneous installation package build number.

The above has a mistake. The way is for 46815, not 49215: The CRC32 and offset aren't OK. The right way:

Setup: setup_little_nightmares_ii_5.7_(64bit)_(46815).exe
GOG ID: 54362850712970995 (05/07/2021 07:09:58 AM UTC)
File: Helios/Binaries/Win64/Little Nightmares II.exe (69,623,752 bytes)
Offset: 051FBB1
String: 0084C075244C8D05
Replace: 75 by EB

Setup: setup_little_nightmares_ii_1160_(64bit)_(49215).exe
GOG ID: 54652863563400612 (08/19/2021 07:05:38 AM UTC)
File: Helios/Binaries/Win64/Little_Nightmares_II_Enhanced-Win64-Shipping.exe (89,835,008 bytes)
Offset: 0A1D0DD
String: 0084C075244C8D05
Replace: 75 by EB
Add to Shortcut Target: "-dx11" after "exe"

CRC32, MD5, SHA1 before the edit:
CRC32 (Little Nightmares II.exe) = 150bf553
MD5 (Little Nightmares II.exe) = 4e4a99b93c938755179f86ae9a572e56
SHA1 (Little Nightmares II.exe) = 2883f1559f3772647708aa29209919857ea79ae5
CRC32 (Little_Nightmares_II_Enhanced-Win64-Shipping.exe) = 14e95cf9
MD5 (Little_Nightmares_II_Enhanced-Win64-Shipping.exe) = d1cde4cc522e025388eed25a3229b772
SHA1 (Little_Nightmares_II_Enhanced-Win64-Shipping.exe) = 88f1d2c4e5dbd4eeef0e31d5127007e736788916

CRC32, MD5, SHA1 after:
CRC32 (Little Nightmares II.exe) = 3cd3bb97
MD5 (Little Nightmares II.exe) = 0df132f58cd12926346361bb06e78818
SHA1 (Little Nightmares II.exe) = 19966f1813c00bebb0f6a9631efea8c96f787d4b
CRC32 (Little_Nightmares_II_Enhanced-Win64-Shipping.exe) = af57163a
MD5 (Little_Nightmares_II_Enhanced-Win64-Shipping.exe) = 6eac6fe3ca4c5b903b39cbbc6f29eafa
SHA1 (Little_Nightmares_II_Enhanced-Win64-Shipping.exe) = c0efda3ff5ee1c5e2672eb95d7f1275835246068

Thank you! Fixed.
I really managed to somehow misplace build numbers.

Installer: setup_little_nightmares_ii_1162_(64bit)_(49574).exe
GOG ID: 54696191638893919 (27/08/2021 14:20)
File: Helios/Binaries/Win64/Little_Nightmares_II_Enhanced-Win64-Shipping.exe (89 837 568 bytes)
Offset: 0A1D0DD
String: 0084C075244C8D05
Replace: 75 with EB
Add to the Shortcut Target: "-dx11" after "exe"

CRC32, MD5, SHA1 before the edit:

CRC32 (Little_Nightmares_II_Enhanced-Win64-Shipping.exe) = BF2D5468
MD5 (Little_Nightmares_II_Enhanced-Win64-Shipping.exe) = 177AC762CBF739F4D24B99E25297F7B0
SHA1 (Little_Nightmares_II_Enhanced-Win64-Shipping.exe) = A9C3AFCD678115638DDDCB36C4AF4D4A63F5DA5B

CRC32, MD5, SHA1 after the edit:

CRC32 (Little_Nightmares_II_Enhanced-Win64-Shipping.exe) = 0B5BB0FA
MD5 (Little_Nightmares_II_Enhanced-Win64-Shipping.exe) = C78205B6909B4F6714D183E28A4D33B4
SHA1 (Little_Nightmares_II_Enhanced-Win64-Shipping.exe) = 9C6DB03B22D9ECAF75DFE1C7112F8A2D75192E63

These are the modifications that must be done to run version 1165 (52002) under Windows 7:


Installer: setup_little_nightmares_ii_1165_(64bit)_(52002).exe
File: Helios/Binaries/Win64/Little_Nightmares_II_Enhanced-Win64-Shipping.exe (89,846,784 bytes)
Offset: A1D21D (or search this: „Àu$L)
Replace: 75 with EB
Add to the Shortcut Target: "-dx11" after "exe"