Hi,
c:\windows\system32\config\
regback exists but it is empty, there are no files in it
On the other hand, I have found an image of the Notebook's partition before I have installed all the software (it was in summer 2022). I could try and export all the registry settings related to the services which were changed and import them to the registry hive of the current system. Will take a while, but I think worth a try.
I will check the srttail.txt as well.