Similar by odd problem with PNG files also. They display properly until I give the PNG a URL-Link and then the PNG turns goofy and looks like a GIF file in that the shadow behind text turns black and poorly displayed… not ok. So, I use JPG and this goes away (I just have to make the background color in the JPG to the background color of the page so that the float looks right.)
PNG files are not being handled properly anymore for some reason. I think this may be WP 3.5 problem and not the plugin – but I am guessing.
