"Komplex" was the name of an over-ambitious project in Blitzbasic 3D that was planned to be an "Ultima Underworld" like game with ego-perspective and RPG-elements.
The inventory-system was designed to resemble "Ultima 8: Pagan", with drag'n'drop-support.
If you're interested, you can watch a gameplay-video on Youtube here. The project's status is 'on ice', probably forever, due to Blitz3D being hopelessly outdated.