As far as your "can't use booleans... greyed out" goes... Sounds to me like you either; Are in the main assembly room and are attempting to boolean and only have selected ONE object or perhaps you have selected a grouped object. Create a scene with 2 spheres and have them intersect. Using CTRL, select both spheres and then you will see the boolean choices are available. Or; You are in the vertex modeling room and are trying to do a boolean subtract, and boolean subtract is 'greyed' out. You need to SELECT ALL in the vertex modeling room and then hold CTRL + ALT... while holding CTRL + ALT click on a vertice of the object which you wish to REMAIN, it will then turn yellow(the vertice).... You will now find that boolean subtract is not greyed out anymore. ****** A word about booleans..... Don't use them if you don't have to.

I am a very unique person... Just like everyone else