It does not require any "software", to the computer it looks like a USB drive, which it is. So you just copy your movies to it for viewing.
It works fine and handles very many video formats. My wife likes movies, so, I hope, she will enjoy it.
When it booted up, it looked kind of suspiciously linux-y with nice blue colors and menus. So I did some searches and learned that it is indeed a Linux device. It runs Linux OS inside. Cowon used GPLed software, so they were obligated to release their source code. Here's something I found for a previous player.