All-In-One. It shows Recently written, Recently viewed, Random, Mostly & Rarely Viewd, Mostly Commented posts with thumbnail in your style.
Check whether you had optimized your database. Remove sub versions of your posts. It'll not only help to extract exact image but will decrease loading time of your blog.
Check whether you have PHP GD library installed.
No, It supports only jpg,png and gif. I hadn't tested it for others.
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