you're gonna have to shut off your internet, otherwise the DM wont recognize the OS. if it still doesnt recognize it, you have to keep installing the OS to the computer and opening DM and connecting the bb until it does recognize the OS.
i would read up on that link i gave you on how to install a new OS first and then you need to download the os from the "OSbeta" forum and install it to your computer. that link will give you step by step of what you need to do. i would upgrade to that .57 that your DM is telling you about, just to see kinda how the process is, and then tackle the 5.0 a different day.