'The release note left in there was an unfortunate oversight,' he writes. As discovered by NeoGAF, the release notes for the new version contain the line: 'Ripped out the Split Screen code and Motion Controller code.'
A mod for the Games for Windows Live version enabled the functionality, but code missing from the new Steamworks version means that the same mod no longer works. The problem is splitscreen-a feature Resi 5 PC has never officially supported.