I don't know if this is usefull to post here,
but my Gabriel Knight 3 (3 disc version,original)
installed and played well
(so far) on my Windows 10-64bit without an installer patch
(or anything else)
Installed in: 1.comp mode Windows XP (service pack 2),
2.Ingame went to graphic options, selected primairy driver,
selected 1024x768, 3.advanced options: texture high,Lighting high
And than ... the game crashed, I had to restart the pc, but
after restarting everything seems to work fine!