Is there a method, view scheme or plug in available for MC12 that will display the data collected and held in the tags of the MP3's (or whatever) in a seperate window. At the moment I can only access them via comments field etc...
It sounds to me like what you want is the Track Info display, assuming all you want is to view (not edit) the track data.
Start the music playing and then switch to Playing Now. In the display area (where the cover art or visualizations show up, not the file list), right click and choose Set Display --> Track Info --> (choose one of them). There are a few default Track Info plugins included with MC, but you can create your own or download ones that others have created. One of my favorites is the All I Need Track Info Plugin, which you can download here:
http://yabb.jriver.com/interact/index.php?topic=35963.0If you download it, simply unzip it and put the folder in
C:\Program Files\J River\Media Center 12\Visualizations\Track Info\. For this particular one, it's also good to "enable scrollbars" in the Track Info window. Simply right click with the Track Info plugin showing and choose Enable Scrollbars. Then you need to restart MC to see them (or maybe just stop and restart playback, I'm not sure).
Once you find one you like, you can right click on the display area and choose Detach Display. This will give you the Track Info in a separate, resizable window that you can put wherever you want.