A question about the Protean ability Beast's Skin

[Aurumae]

I'm curious how this ability interacts with the other Protean abilities. For example, let's say I use Beast's Skin to turn into a Bear. The Discipline reads "While in animal form, the vampire can use her Disciplines as normal". Does this mean I can then use Unnatural Aspect as normal to grow a pair of wings? Can I become a flying Bear?

What's more, the Devotion "Force of Nature" (p144) reads "the vampire gains as many of the advantages of Predatory Aspect, Beast’s Skin, and Unnatural Aspect as she wishes". I'm curious what an "advantage" of Beast's Skin is in this context? Could I pick and choose stat changes from my various stored animal forms?

[Tessie]

I'm curious how this ability interacts with the other Protean abilities. For example, let's say I use Beast's Skin to turn into a Bear. The Discipline reads "While in animal form, the vampire can use her Disciplines as normal". Does this mean I can then use Unnatural Aspect as normal to grow a pair of wings? Can I become a flying Bear?

Yes.

What's more, the Devotion "Force of Nature" (p144) reads "the vampire gains as many of the advantages of Predatory Aspect, Beast’s Skin, and Unnatural Aspect as she wishes". I'm curious what an "advantage" of Beast's Skin is in this context? Could I pick and choose stat changes from my various stored animal forms?

For Beast's Skin each separate animal form is its own advantage. But you can change reflexively between forms to gain the advantages of several during a single turn; just not at the same time.

[Marcus]

I'm curious how this ability interacts with the other Protean abilities. For example, let's say I use Beast's Skin to turn into a Bear. The Discipline reads "While in animal form, the vampire can use her Disciplines as normal". Does this mean I can then use Unnatural Aspect as normal to grow a pair of wings? Can I become a flying Bear?

Yes for the 1st question although the wings are intended to allow an human being to fly at his full speed. A Bear should be far more heavy so someone could argue it's too weight to fly with such wings. But generally speaking, yes. You could have a Bear with unnatural claws, or able to slip within tiny fissures etc.

What's more, the Devotion "Force of Nature" (p144) reads "the vampire gains as many of the advantages of Predatory Aspect, Beast’s Skin, and Unnatural Aspect as she wishes". I'm curious what an "advantage" of Beast's Skin is in this context? Could I pick and choose stat changes from my various stored animal forms?

Yes. and each turn from a different animal. You could be a Bear with horrid talons, able to crawl on vertical walls and the very next turn a cat, each time moving as many dots from the ones related to the specific form, as you wish.

[Live Bait]

By a strict reading of the rules I believe you can take as many aspects as you want so all of them would seem to be a valid choice, a flying bear able to squeeze through tight spaces and do lethal damage to vampires seems to be valid.
If I’m wrong please let me know.