variable not set in media_mover.inc line 146

When I run a cron job, it's not doing anything because there's a legacy variable variable_get('mm_node_types', null) still in use here. My guess is that it works on your installation because the variable is set, but in the existing version this has moved on to $configuration['mm_node_types']... I noticed there's a TODO there to this effect, I think the only thing that needs to be changed is updating variable_get('mm_node_types', null) to $configuration['mm_node_types'].