Learnt/inferred a few things here [correct me via comments if I am wrong conceptually; note that these have worked for me] -
- Win key is called/referred to as the 'super key'
- You may have to get xmodmap to explicitly recognize the key.
- You can get the keycode for any key using 'xev' command, as discussed here: http://forums.fedoraforum.org/showpost.php?s=9af5fdea1041e19ff96815fb3470f904&p=913923&postcount=9
- Once you find out the keycode for you Win key, you can get xmodmap to 'recognize' it as noted in http://forums.fedoraforum.org/showpost.php?s=9af5fdea1041e19ff96815fb3470f904&p=913308&postcount=3
- Then, configure Win+key combinations via System > Preferences > Keyboard Shortcuts.