I understand a bit about DVD burning, but am also not an expert. As far as compressed or uncompressed, I don't think the DVD really knows or cares. A data file is a data file. It's just the application(s) that you run that deal with the files (such as the clopp file) as compressed data and know to extract what they need from it. I know nothing at all of growisofs, whatever that is, and while I read the remastering forum I have yet to remaster anything (even a CD) so I don't want to pretend to be the expert here. But the file size of the clopp file is a DVD file restriction, and I would think that cmg files would be a good way around it (another might actually be to create a second compressed clopp file, but cmg files strike me as a better way to approach it). Perhaps Probono can give us his thoughts on all of this.