Q1: This card has multiple effects that are triggered when it plays, in what order can they be activated?
Since they are triggered simultaneously, the player can choose the order in which they are to be activated.
Lv.6 Necromon BT20-079 SR Mega | Virus | Ghost/LIBERATOR <Security A.+1> <Execute> (At the end of your turn, this Digimon may attack. At the end of that attack, delete this Digimon. Your opponent's unsuspended Digimon can also be attacked with this effect.) [On Play] [When Digivolving] Delete 1 of your opponent's Digimon with the lowest level. [On Play] [On Deletion] You may play 1 level 5 or lower Digimon card with the [Ghost] trait from your trash without paying the cost.
Lv.6 Necromon BT20-079 SR Mega | Virus | Ghost/LIBERATOR <Security A.+1> <Execute> (At the end of your turn, this Digimon may attack. At the end of that attack, delete this Digimon. Your opponent's unsuspended Digimon can also be attacked with this effect.) [On Play] [When Digivolving] Delete 1 of your opponent's Digimon with the lowest level. [On Play] [On Deletion] You may play 1 level 5 or lower Digimon card with the [Ghost] trait from your trash without paying the cost.
Lv.6 Necromon BT20-079 SR Mega | Virus | Ghost/LIBERATOR <Security A. +1> {{Execute}}. [On Play] [When Digivolving] Delete 1 of your opponent's Digimon with the lowest level. [On Play] [On Deletion] You may play 1 level 5 or lower Digimon card with the [Ghost] trait from your trash without paying the cost.
Lv.6 ネクロモン BT20-079 SR 究極体 | ウィルス種 | ゴースト型/リベレイター ≪Sアタック+1≫≪エグゼキュート≫(自分のターン終了時、このデジモンでアタックできる。このアタック終了時、このデジモンは消滅する。この効果ではアクティブ状態の相手のデジモンにもアタックできる) 【登場時】【進化時】最もLv.の低い相手のデジモン1体を消滅させる。 【登場時】【消滅時】自分のトラッシュから、特徴に「ゴースト型」を持つLv.5以下のデジモンカード1枚をコストを支払わずに登場できる。