DRM removal software is intended to be used on legally purchased files. Please do not abuse rental licenses.
What is your IBX version? Mirakagi doesn't work with IBX 11.6000.7000 or later.
Most probably you have to downgrade your WMP (however all your licenses will be deleted so make sure you can restore them). Uninstall anything related to Napster and any WMP upgrades it forced.
You can also install a fresh copy of Windows XP onto virtual machine.
Please use search to find more details.
As for drm2wmv, you may read about another concole application freeme2. It should help you to understand how to work with CLI apps.
Related threads:
Windows Media Player 10/11: How to determine IBX version in Windows XP
Freeme2 - freeware open source software to remove DRM protection from Windows Media .WMA audio files and .WMV video files.