I just compared original retail 3CD v1.0029A (Safedisc v2.70.030 protected) version to the electronic (GoG v1.005A) version of the game. Installed retail version in one folder and electronic in another. Then compared files in these folders using Total Commander. Found very few critical differences (5 files - 'configtool.exe', 'div.exe', 'DivDialogSystem.dll', 'Osiris.dll' and 'slash1.dll'). All other files (except a few editable configuration files) are identical.
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