They said their format is ePub with DRM. And that's true. But... The file you download in your browser is an obfuscated XML file, which Adobe Digital Editions parses to get a URL, which it then uses to download the DRMed ePub file. Only Adobe Digital Editions can parse the XML properly, and it requires .NET framework 4.0 to run. Good luck running that in Wine, and for Windows it's a 200 MB download or so.
Also it looks like the ePub file DRM is of a sort that only allows it to be read on one application... you guessed it, Adobe Digital Editions. And only on one reader, computer, or other device.
All this so I could pay the authors for their work. And what's sad is that, just searching for said books on DuckDuckGo turns up half a dozen torrent sites with pirated versions. They make easier to read books by stealing them, and ripping off the authors, than by paying for them! No bloody wonder they have a piracy problem. Great job, assholes!
