I’m testing on an iPhone 4S. I do not have a 5 or 3G so I can’t see what happens on those screens.
I just removed the startup image url from the “640×1096 (iPhone 5 and 2012 iPod Touch)” and reloaded my site and the startup screen for the iPhone 4/4s finally did appear.
Hopefully this is a quick fix for the plugin author and we can get the 5 startup screen loading as well.