Check this out.
http://www.zorba.us/?page_id=676
I've been trying to deal with images in my ebooks although on a significantly lesser scale.
It shouldn't be that difficult to do a four panel graphic or conversely to include an image that is 600x600 (more or less) and set the width max-width: 600px for the entire panel.
I think the key is to let css scale the height and width of the image. Epub supports many css properties
http://www.idpf.org/2007/ops/OPS_2.0...tml#Section3.3
Once you have the template and images no more than 63K you can let the screen size determine their width and height. The image can be large (800x600 or larger), and then you can specify the maximum height/width for each image.
Keep in mind that ipad will have a dimension of 1024x768. You also need to test the 800x600 dimension.
This sounds like a lot of trouble, but once you have done the css for your template and made sure your images conform to the requirements, you should be able to get them to work.
(Then when you have epub, you can use calibre software to convert to mobipocket format).
The question I wonder is how many images can go in a single epub file without the ebook device starting to choke. I have a feeling this is going to differ according to the device.