Joachim,
Please consider revising your review. I’ve no doubt it may not be working on your site but there are at least three reasons it may not which have absolutely nothing to do with the plugin. Because I can assure it works perfectly on several sites I have installed it on, and it is programmed in a very standard WordPress way.
1. It uses an external service by WordPress.com, if that is down the browser shots may not work.
2. You may have a plugin that conflicts. Plenty work but do things in some terrible ways. Which break things for other plugins. Try disabling your plugins and retesting.
3. Your host may restrict certain php functionality.
