Placing Flash triggers the effect, causing the attack to miss. After that, it doesn't particularly matter what happens to Flash.

Hmm. I agree and disagree at the same time, oh well. XD

Not correct. The miss is not dependent in any way on him actually being placed. The effect triggers, and you resolve as much of it as possible. The placement does not happen first, it all happens at once. It doesn't much matter if Flash is removed once you choose the square you want to place him in, the miss is already happening.

When effects happen simultaneously, the active player chooses the order

It doesn't matter,
Go ahead and remove him first, the full effect will still resolve.

If you remove him first, there is no effect on the map. <_<

btw, I WANT this to work because I really like this Flash. I'm just understanding the rules differently.

Irrelevant. Placing him caused the effect to trigger. So the effect will resolve.

Following your logic, if my character hit and damaged a Mystics character and KO'd it, my character would not take any Mystics damage. But it does. Because the Mystics TA was triggered by the attack damage. Doesn't matter that the Mystics character is no longer on the map/is KO'd.

And again, this is not "effects", plural. This is one singular effect. There's nothing to choose the order of.

And as we've already said, and quoted, several times, what you're trying to argue is irrelevant, because the trigger still resolves.

The triggering event is a friendly character being hit by an attack, not the placement. If it were, then there would be some room for interpretation, and we'd need to know whether the placement can ever actually occur in this scenario, because the miss couldn't happen unless the placement did. The placement is part of the resolution of the trigger, just like the attack miss. Not a distinction that will matter, functionally, 99.9% of the time, but is still important to understand.

So someone happened to call Flash in and an attack is made on a character 6+ squares away.

You decide to go ahead and use this trait.

Until Flash is placed, he is not 6+ squares away so he's not going anywhere, right?

Once you decide to use the trait, Flash must be placed first, right? I mean, he's not 6+ squares away from the figure that called him in until he's actually placed 6+ squares away, right?

That's it.

Once he's placed he's removed, but he's been placed and that is all that is required for the trait to take effect.

There is no question of order here. Everything happens in the only order that it can happen.

Question: in this scenario does the opponent get Flash's (60) pts?

The Flash is removed due to the ID Card's effect, so no, the opponent does not score his points.