Richard Sampson

Q:Can I activate the "when an effect trashes this card from the security stack" effect when this card is revealed from the security stack or when searching/looking at this card from the security stack?

A:No, you can't. You can only activate the "when an effect trashes this card from the security stack" when this card is directly trashed from the security stack.

Q:What does "if there're X or fewer total cards in both players' security stacks" mean, exactly?

A:It refers to when the total number of cards in both you and your opponent's security stacks is X or fewer. The text "if there're 6 or fewer total cards in both players' security stacks" would include when there're 3 cards in both players' security stacks, 2 cards in your security stack and 4 cards in your opponent's security stack, etc.