I,m using the bryce 5 handbook at school and am working with the metaballs. when i tried to use negative and positive ones, it worked the first time ( cutting it in half) but the second time i tried it would not work. now the negeative metaballs don't appear to be invisible. Also the book says that clicking shift and the metaball icon will make a negative metaball but it doesn't, ( had to go through attributes?