I just pushed out the latest version of my plugin Facebook Like Thumbnail,
v0.3.1 to be precise, on WordPress.org plugins repo. It should show up in your WordPress admin shortly if you are using it and if not, then here is yet another reason to try the plugin out if random or unwanted images show up for your WordPress site when links are liked or shared on Facebook.
The new version is a complete rewrite and is really good at figuring out the context specific image to use for different types of pages. It also deals with situations where earlier version would run into compatibility issues with other plugins. And last but not least, this version is developer friendly in case you want to short-circuit the logic, you are able to do so now. All power to you.
Hit me up if you have any questions. And one real good of piece of advice that I can't mention too much is - Facebook maintains a cache of images selected for every URL (usually 24hours), so your new images won't show up right away, but eventually they will. Facebook has a really nice tool to debug your URLs outside of their cache to test the image being selected for display - https://developers.facebook.com/tools/debug
If you are looking for premium support - get in touch with me via my contact form.