If your dds files aren't already compressed CM will compress them. I've never had a problem and not many people report problems either. It's just pretty standard file compression very similar to Windows own built in, very mature and reliable. Saying that, I did see on FB the other day that someone is blaming the compression for messing all of their skins up

. Even a system power cut during the compression process shouldn't mess all skins up in all cars *shrug*. Like anything important though, back up the skins you can't get back and give it a shot. Seriously like other people have said, if you haven't yet tried it you will be surprised at how much space you will save. Vital if you have all of your cars and tracks on an SSD imo.