Have you installed Windows Media Player 11 Beta. I was having a similar problem that you are reporting with the software appearing to start up but not loading properly. Initially, when I installed Windows Media Player 11 on my PC (Dell Deimension 4550 with fairly standard specification running Windows XP), I was no longer able to transfer music to my NWA-3000 device. I reinstalled Sonic Stage CP but after this could not even open the software properly. I rolled back to WMP10 and reinstalled Sonic Stage CP and this has resolved the problem
