Q1: Can I use this card's Main effect to place this card in the digivolution cards of a Diaboromon Token that was played by this effect?
No, you can't. Cards can't be placed under tokens.
Q2: What does "you win the game" in this card's Start of Your Turn effect mean, exactly?
When this effect activates, the player that activated the effect wins the game.
Q4: Can I use the End of Opponent's Turn effect in this card's inherited effects to place this card itself in the battle area when this card is in a Digimon's digivolution cards?
Yes, you can.
Doomsday Clock BT17-100 U [Security] Add this card to the hand. [Main] Play 1 [Diaboromon] Token without paying the cost. Then, place this card as the bottom digivolution card of 1 your Digimon with [Diaboromon] in its name and without [Doomsday Clock] in its digivolution cards. (Digimon/Cost 14/Lv. 6/White/Mega/Unknown/Unidentified/3000 DP) [Start of Your Turn] If your battle area has 4 placed [Doomsday Clock]s, you win the game.
Doomsday Clock BT17-100 U [Security] Add this card to the hand. [Main] Play 1 [Diaboromon] Token without paying the cost. Then, place this card as the bottom digivolution card of 1 your Digimon with [Diaboromon] in its name and without [Doomsday Clock] in its digivolution cards. (Digimon/Cost 14/Lv. 6/White/Mega/Unknown/Unidentified/3000 DP) [Start of Your Turn] If your battle area has 4 placed [Doomsday Clock]s, you win the game.
Doomsday Clock BT17-100 U [Security] Add this card to the hand. [Main] Play 1 [Diaboromon Token] without paying the cost. Then, place this card as the bottom digivolution card of 1 of your [Diaboromon] without [Doomsday Clock] in its digivolution cards. [Start of Your Turn] If 4 [Doomsday Clock]s are placed in your battle area, you win the game. --- [All Turns] When this Digimon would leave the battle area by an opponent's effect, by deleting 1 of your other [Diaboromon], prevent it from leaving. [End of Opponent's Turn] Place 1 [Doomsday Clock] from this Digimon's digivolution cards in the battle area.
終末のトケイ BT17-100 U 【セキュリティ】このカードを手札に加える。 【メイン】「ディアボロモン」(デジモン• 14コスト• Lv.6• 白• 究極体• 不明• 種族不明• DP3000)のトークン1体をコストを支払わずに登場させる。その後、このカードを進化元に「終末のトケイ」がない名称に「ディアボロモン」を含む自分のデジモン1体の進化元の下に置く。 【自分のターン開始時】自分のバトルエリアに置かれている「終末のトケイ」が4枚あるなら、自分はゲームに勝利する。 --- 【お互いのターン】このデジモンが相手の効果でバトルエリアを離れるとき、他の自分の「ディアボロモン」1体を消滅させることで、離れない。 【相手のターン終了時】このデジモンの進化元から、「終末のトケイ」1枚をバトルエリアに置く。