Bladewind/Gift of Heaven/Falling Frost questions

[Corwin]

It's been a while since my Dom2 days, so I've partly forgoten few particular details- therefore I have few spell-related questions, which I hope somebody will be able to answer.

Remind me please - bladewind damage is condidered
to be "normal" type, not magical, correct?

If this is the case, then "Arrows Fend" spell should give 80% ptotection from damage done by Bladewind, correct? (IIRC "air shield" , which is basic spell that "arrows fend" cast on all ubits, only protects against nonemagical attacks.)

And what about "Gift From Heaven" - are they simply rocks or do the do magical daage as well?

Last question - do I remember correctly that "Falling Frost" damages units regardless of their cold resistance, unlike "falling fires", to which fire-resistant units are ummune? How effective are nummble units vs "Falling Frost"?