Trying to set up BT in virtualbox and I am reading some posts about "guest additions" that help run BT in virtualbox. How do I find these and install them? I tried a google search but didnt get much as far as BT goes. I did find some info on installing them in Ubuntu, but when I go to the Devices menu and click the install addons button, an error message appears about forcing an umount. Any ideas about this?