crox 4, solo project - nothing (April 1990).
crox 18, En Passant - location 2, Sint-Pietersnieuwstraat 84 (September 1991).
crox 51, Open Deuren (1996).
Installation window May 2006, location Onderstraat 26.
The first contribution of Hugo De Leener (crox 4, mei 1990) comes to nothing. Frank and Hans document this nothing, even something which is nothing needs to be documented. There is indeed a video of crox 4.
For his second solo project and his participation in group projects like En Passant and Open Deuren he contributes practically identical work. There are internal variations within the works.