Using the plugin from my desktop on my wordpress blog is ok either in IE, Chrome and Firefox.
I use the start and end time line to display only extracts from youtube videos.
It works well and easy to use.
But I also set a plugin to go mobile called "wp mobile detector" and when I watch the video from my iphone the video starts from the very begining regardless of start time and stop time.
I hope it is a minor bug that can be fixed quickly..