Can I roll Impervious before the Trait?
If i have the IG and i have the Orang Gem active, can I roll Super sense, then Impervious and finnally the trait?

You are going to have to quote the Ability in question.

To be helpful:

Yes, you can make all of your defensive rolls before the trait. You only roll for adaptive armor if you would take damage. SS, imperve, etc will stop you from taking damage in various ways

Assuming you have all those powers you not only can but actually must roll for them. Super Senses first, then Impervious if SS fails, then the trait if Impervious fails would I believe be the required order: Super Senses is definitely first and I think based on wording Impervious ("is dealt damage") will come before Adaptive Armor ("would take damage").

Active player chooses, I believe, any situation which order something happens when it is multiple things happening at once.

-PC

Pretty much positive this gent is correct.

Pretty sure rystalquinn is incorrect. Active player only chooses when they happen at the same time which is not the case here.

yep, you get them all if you have them. If you make the super senses roll, then you were never hit to begin with. If SS fails but you make the impervious roll, damage was reduced to 0, so you did not take any damage to trigger the trait. If the Impervious roll fails, then the damage would still be reduced by 2, if you still take damage after all of that, then the trait would kick in.

Correct. There are various steps preceding taking damage which is when Adaptive Armor will activate. If you can avoid damage somehow in one of these steps (you Shape Change to avoid the attack entirely, use Super Senses to avoid the attack when hit, and finally use a damage reduction ability to possibly reduce damage to 0) the armor will never activate; it only checks for actual damage and not just if hit.

Just a clarification: the above is true for any case where multiple effects occurring at the same time, other than multiple damage reducers*. In the specific case here, though, the effects don't actually occur at the same time.

*with multiple damage reducers only one can be used and the controlling player chooses which.