Warning in finder_wizard_finder_render

I installed the finde module and the default finder demos /content-finder and /people-finder throws the following warnings, resulting in the search not working.

Warning: Parameter 1 to finder_wizard_finder_render() expected to be a reference, value given in call_user_func_array() (line 823 of …/includes/module.inc). =>

Any idea what is going wrong or why this module is not working for me?