When my opponent's Digimon attacks and checks my security, I activate this card's effect to gain 1 memory, moving the memory counter to 1 on my side. Does the attack end, even if my opponent's Digimon has checks remaining from <Security Attack +1>?

While this Tamer is in my battle area, my opponent's Digimon checks my security stack and flips over [BT1-107 Holy Wave]. Its [Security] effect activates, adding a card to my security stack. The number of cards in my security stack remained the same, but can I still suspend this card to gain 1 memory?

While this Tamer is in my battle area, I use [BT1-087 Matt Ishida]'s effect to add a yellow card from my security stack to my hand, triggering <Recovery +1 (Deck)> and adding a card to my security stack. The number of cards in my security stack remained the same, but can I still suspend this card to gain 1 memory?

If my opponent uses a card like [BT2-020 Gallantmon] to trash a card in my security directly, can I activate this card's effect?

If I activate an effect like [BT4-104 Blinding Ray] to remove cards from my own security stack, can I activate this card's effect?

If this card is played by its [Security] effect, can I suspend it to gain 1 memory?