If your opponent's character was switched to resting with this ability, your opponent draws a card. If your character was switched to resting with this ability, you draw a card.

It means the character cannot be chosen by abilities like "Choose one character on your opponent's front line and sideline it" which include the "choose" instruction.

If a battle occurs, it will activate after the battle ends. If damage is dealt to the player, it will activate after the trigger check ends.

It refers only to the ability "[When Played] If you have used an event card this turn, choose up to one of your AP cards and switch it to active." It does not refer to other abilities on the same card.

It means the character cannot be chosen by abilities like "Choose one character with 3000 or less BP on your opponent's front line and sideline it" which include the "choose" instruction.

If the maximum number of cards that can be placed on the line changes and the number of placed cards exceeds that limit, place any one card from the line into your removal area, then reconfirm the maximum number of cards that can be placed on the line. After reconfirming, if the number of placed cards still exceeds that limit, repeat the previously described management.

When choosing a character for abilities like "Choose one character with 5000 or less BP on your opponent's front line and sideline it" which include the instruction to "choose" a character, this ability forces the player to pay 1 AP as an additional cost in order to choose this character. The player may instead not pay and choose a different character. Or, if the option is allowed, they may choose zero characters. If 1 AP cannot be paid, this character cannot be chosen.

No, you cannot. The two characters must be played or Raided simultaneously.
Stack the character with ■Raid■ on top of the Raid base character on your energy line, place another card from your energy line into your removal area, then play the second character onto your energy line.
Then, after performing "Switch to active. May move to the front line" management on the Raided character, manage any [When Played] abilities on the played and Raided characters in any order you want.

Yes, you can.

No, it is not lost.

Yes, it does. If you activate it twice, 2000 is added to the specified BP range you can choose.

Yes, you can.

Yes, you can.

Yes, you can.

When your opponent chooses this character with a ▼Special Trigger▼ ability, it is not sidelined, and they add the card with the ▼Special Trigger▼ ability to their hand instead of placing it into their sideline.