I only noticed the 404 error on more.png. I just copied the image to the folder where it was missing. I manually put the sociable code in my templates, so I didn’t find code leftovers after removing. I certainly hope that the plugin doesn’t go modify your pages! If it does then I hope it cleans up after itself on uninstall…
It’s sad that these errors happen. It is (or was) a fairly good plugin, but the bad URL errors, bad formatting, etc., really leave a bad impression on attention paid to, and quality of, coding.