I’ve re-made this plugin into something more complete, using the current version of the Logi SDK. It now supports blueprint programmability for force feedback effects (you can even use curve assets to control various parameters etc). Also, all axes and buttons are now present as inputs (under Game Controller) for input mapping as well as events in blueprints.
Here’s the project source: https://bitbucket.org/whiten01se/logitechg27plugin. Enjoy.
One thing is worth noting: I didn’t bother to implement a Win32 path for this plugin, but you can do that yourself if you really need 32bit support.