alcaray: There have been several patches since the release version. This patch is only the last one. It cannot be applied to the release version directly. You would need all of the patches and then apply them in the correct order.
Regenerator: There have only been two hotfixes, one on August 4th and then one today on 8th
https://steamdb.info/app/1086940/patchnotes/
All the other changes were just to the register or soundtrack, nothing with the game files.
That's correct for the Steam version, but on GOG there was a smaller update (~16mb) that preceeded the actual patch 1 download, which appears to have updated some files of the Larian launcher and bumped the version number upto v4.1.1.3624901.
I have the game installed through Galaxy, and this is what its version history currently looks like:
v4.1.1.3630146 - Patch Patch0_Hotfix2
v4.1.1.3624901 - Patch v1 <--- they finally released an offline installer for this
v4.1.1.3624901 - Patch <--- but they forgot to include this part
v4.1.1.3622274
Don't ask me why they split it into two updates on GOG, but I'm not sure it was intentional, because it resulted in some of us ending up with a "Data Mismatch" error on the Larian launcher.
It looks like they FUBAR'd again with the Patch 1 offline installer, seemingly forgetting that they should be including the entire update, so that it patches the game directly from "v4.1.1.3622274" to "v4.1.1.3624901 - Patch v1". Either GOG or Larian are drunk, or someone needs to urgently send them a resupply of caffeine...