Booolean objects look just like any other resident natural objects in Bryce....  not the obj files type.

Root out is the same as "find and remove"....  How you tell it's a Boolean object is by:

pointing you mouse arrow on any object and press ctrl+shif and click.. a small menu comes out and tells you the name of the object and says "mesh" or "cube, cone, sphere" or "meta ball"
see image...

cube, cone, sphere are the boolean objects.... you can not boolean mesh objects... meta ball work a bit different...  There is a list that you can see... but it is raw.. no editting of this persay list..   But one can name parts of the objects via the "object Attribute" function..  you can see the little "a" on that verticle list next to the pop up menu....

hope this was helpful...

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