The plugin is purposed for assigning adverts after user registration. It sets adverts from guest to user basing on email from advert.
There are no parameters to set. You just need to enable the plugin.
Once you enable the plugin all adverts that were added by guests will be automatically added to their accounts when they register.
Learn more on how to let users submit adverts as guests from this article: How to allow unregistered users to post and edit ads