Rulings
Q1: What position on the memory gauge does "if you have 1 or more memory" refer to?
It refers to when the memory gauge is at 1 or further to the left on your side.
Q2: What does "can't ... activate When Digivolving effects" mean, exactly?
This effect prevents When Digivolving effects on cards from activating. Triggered When Digivolving effects can no longer activate when a card digivolves or when effects such as "activate that card's When Digivolving" effect" activate.
Q3: I used a card affected by "can't ... activate When Digivolving effects" to attack. Can I activate that card's When Digivolving When Attacking effect at such times?
Yes, you can. The effect can activate if it's triggered upon the When Attacking timing.
Q4: If a card is affected by "can't ... activate When Digivolving effects," can it activate its own When Digivolving effect using an effect such as "activate 1 of that card's When Digivolving effects"?
No, it can't be activated.
Q5: If a card is affected by "can't ... activate When Digivolving effects," can another card's When Digivolving effect be activated using an effect such as "activate 1 of that card's When Digivolving effects as an effect of this card"?
No, it can't be activated.
Q6: Can I use "activate 1 of that card's When Digivolving effects as an effect of this card" on a card that isn't affected by "can't ... activate When Digivolving effects" to activate the When Digivolving effect on another card that's affected by "can't ... activate When Digivolving effects"?
Yes, you can.
Q7: If a card is affected by "can't ... activate When Digivolving effects," can I process just the "by doing X" condition in its When Digivolving effect?
No, you can't.
Q8: A card digivolved into a card that has a When Digivolving When Attacking Once Per Turn effect while "can't ... activate When Digivolving effects" was activated. Does that count as an instance of that effect's X Per Turn even if that effect can't be activated upon the timing when that card digivolved?
No, it doesn't count. The effect can't activate upon the When Digivolving timing, therefore it doesn't count as an instance of that effect's X Per Turn.
Data Sources
Lv.6 MarineAngemon EX8-035 C Mega | Vaccine | Fairy/DS [Digivolve] Lv.5 w/[DS] trait: Cost 3 [Security] At the end of the battle, give 2 of your opponent's Digimon <Security A. -1> for the turn. Then, add this card to the hand. [All Turns] While you have 1 or more memory, none of your opponent's Digimon can activate [When Digivolving] effects.
Lv.6 MarineAngemon EX8-035 C Mega | Vaccine | Fairy/DS [Digivolve] Lv.5 w/[DS] trait: Cost 3 [Security] At the end of the battle, give 2 of your opponent's Digimon <Security A. -1> for the turn. Then, add this card to the hand. [All Turns] While you have 1 or more memory, none of your opponent's Digimon can activate [When Digivolving] effects.
Lv.6 MarineAngemon EX8-035 C Mega | Vaccine | Fairy/DS [Digivolve] Lv.5 w/[DS] trait: Cost 3 [Security] At the end of the battle, give 2 of your opponent's Digimon <Security A. -1> for the turn. Then, add this card to the hand. [All Turns] While you have 1 or more memory, none of your opponent's Digimon can activate [When Digivolving] effects.
Lv.6 マリンエンジェモン EX8-035 C 究極体 | ワクチン種 | 妖精型/DS 特徴に「DS」を持つLv.5:コスト3 【セキュリティ】バトル終了時、ターン終了まで、相手のデジモン2体に≪Sアタック-1≫を与える。その後、このカードを手札に加える。 【お互いのターン】メモリーが1以上の間、相手のデジモン全ての【進化時】効果は発揮しない。