Questions to be answered.

Question 1: If I equip Amulet of Ambition (Equip only to a Normal Monster. If it battles a monster with a higher Level, the equipped monster gains 500 ATK x the difference in Levels (during that battle only). When this card is sent to the Graveyard, you can return it to the top of your Deck.) to a gemini monster on the field and then gemini summon it causing it to be an effect monster will the amulet still be active?

Question 2: If you use Unleash Your Power! (All Gemini Monsters that were on your side of the field when this card was activated are treated as Effect Monsters and gain their effect(s). During the End Phase of this turn, Set all monsters affected by this card's effect) and you have say a Phoenix Gearfried who is already gemini summoned and treated as an effect monster at the end of the turn will that as well be turned face down? Or since it is treated as an effect monster is it completley immune to the effect of Unleash Your Power!?

Question 3: If you have a monster like Infinity Dark in the graveyard and Tribute a Blazewing Butterfly (Treated as an effect monster) equiped with Supervise is it possible to bring back both Blazewing and the Infinity Dark?

Question 4: Can you call priority on Black Brutdragon's effect (Once per turn, you can send 1 Gemini monster from your hand to the Graveyard to select and destroy 1 Spell or Trap Card your opponent controls. When this card is destroyed and sent to the Graveyard, you can select 1 Gemini monster in your Graveyard and Special Summon it. The Special Summoned Gemini monster is treated as an Effect Monster, and gains its effect.) to discard a gemini monster from your hand and destroy a spell or trap card on the field?

Question 5: If Brionic, Dragon of the Ice Barrier uses its effect and you discard the cards, can your oponent use a card like Book of the Moon to flip it face down as soon as you pay the cost and not allow the cards to be returned even though you payed the cost to activate the effect?

Question 6: Does Scrap Iron Scarecrow target a monster? Can you use it against a card like Obelisk the Tormentor if it attacks (Obelisk cannot be targeted by the effects of spell, trap or monster effects)

Question 7: Can you use Unleash Your Power! (Linked the effect above in question 2) if Light of Intervention (Monster cards cannot be Set face-down. Monsters Set in Defense Position are Normal Summoned in face-up Defense Position.) is on the field? If you can will they simply remain face up as effect monsters?

1) No, the amulet will be destroyed, as it isn't equipped to a normal monster.
2) IIRC, it only effects "unsummoned" Gemini monsters, so I don't *Think* it will do anything.
3) The butterfly's effect resolves first, bringing back infinity dark, then, because it was sent to the graveyard, supervise's effect activates, allowing you to bring back the Butterfly.
4) Yes.
5) You can only discard 1 card at a time for Brionac. Your opponent can chain book of moon to the activated effect, but the effect will still resolve, returning the card to the player's hand.
6) Scrap-Iron does target the monster.
7) You cannot activate Unleash Your Power! if Light of Intervention is on the field. If Light of Intervention is chained, Unleash Your Power! cannot resolve and is destroyed. (I have no idea what happens if U.Y.P! is chained to light of intervention.)

Are you sure Brionac's effect is by one at a time? The wording of the effect is "You can discard any number of cards to return the same number of cards from the field to the hand." According to that wording, you discard all the cards you want at first. And then if your opponent chains something so one of the targets is gone Brionac needs a diff target, even if its your own cards.

ya it not one at a time it as many as you want at a time but most people do it one at a time tho

According to the yugioh wikia, they still get returned to the hand.