I was trying to do this manual and by chance I searched the Joomla Extensions site, to my amazement there was a component to transfer content from 1.0.x to 1.5.x!! If you read the instructions provided, you should have no problems. Instead of using the images export function though, I manually copied the images over, but the end result was the same. Thank you very much for this component, when I get some extra money, I'll definately donate.