How can i see the trigger volume in editor class list?

Hi epic:
I want to show the trigger volume class in my editor class list for i can create blueprint actor which inherited it. I have tried to made trigger volume class as blueprintable, and compilation editor . I can create the bp after done these operation. But i found some bp function can not be invoked in blueprint graph. Also if i place one bp actor into my map, and i can not see the size of it. Can anyone show me tips?

  thanks,' 

  zql