text: "Read Level Error Function Pointers Have Moved" error. – GOG.COM SUPPORT CENTER
  "Read Level Error Function Pointers Have Moved" error.
  If you encounter this error, please:
  - Download files from the links below:
  Roguepatch
  Xatrixpatch
  - Open Roguepatch.zip archive and copy the file called: gamex86.dll to the folder called: 'rogue' which is located in the main folder where quake II is installed(default: C:\GOG Games\Quake 2\rogue\).
  - Please overwrite previous file.
  - Now, please open xatrixpatch.zip archive and copy file called: gamex86.dll to the folder called: 'xatrix' which is located in the main folder where the quake II is installed(default:C:\GOG Games\Quake 2\xatrix\).