When you have the image mounted, can you browse through the CD like you would a normal CD? Do you see files, and folders? I've attached 2 text files that contain a directory listing of the files in the root of each CD. If, when you have your images mounted via Daemon, you can see these files (or, really, any files), then it's working just fine. Converting the CDI into another format will not help in anyway whatsoever in extracting, or converting, the files on the discs. Basically, it will almost certainly be easier to create the models and textures yourself, than it would be to create a program that could convert that info for you. Sure, they probably were created on a PC first. But I have never encountered a game that didn't use a proprietary format for its game data. Meaning, in almost all instances, you can't just read the data straight off the disc into Paintshop, or Photoshop, or Quicktime, or Media Player, or Winamp, or 3D Studio Max. You need to figure out a way to decode that information first, and then you need to figure out a way to save that decoded information into a format recognizeable by one of those programs. If you don't have any tools in mind to do this, then there's a good chance the tools you need don't exist.
In all honesty, I hope I'm wrong, because I'd like to pull all kinds of information out of this game... So, yes indeed, good luck. I recommend you start searching for Dreamcast extraction/conversion utilities. I've seen a few, but most of them were to make games self-bootable, aid in ripping the game disc, or convert audio files into ADX format, to help alter/decrease the file size of the ADXs (so that it could easily be burned to a regular CD). Sorry I don't have more information than that. Hopefully it was helpful though. Mouser X over and out.