Image overlay incomplete options

I’m just trying to get the image overlay work and yes, it works good, but the documentation and options for this are very poor.

First of all the plugin says “If you activate this option globally, you can disable it based on your conditions using the fb_og_image_overlay filter”. Sure. Disable it, where? Where is that option? And what is the value that i should give to fb_og_image_overlay, to turn off overlaying?

Secondly, there is no option to select where the overlay image should be put and where not. For example, you possibly don’t need it on a cookies warning page, or the homepage, or a contact page. I think being able to choose where to use it (for example, only posts) would be nice.

Has anyone run into these? And how did you manage?