Also, the extra part of the ring is when you hit with Incap or whatever, you can use Barrier as a free action. He can already use Barrier so he can't gain Barrier again.

It is two separate effects. One effect gives you barrier, this line:

"This character can use Barrier and when it takes damage from an attack, deal the attacker 1 unavoidable damage."

The other effect changes HOW barrier is used, this line:

"When this character uses Barrier, it may use it to place up to 8 squares of blocking terrain."

So, while Sarah cannot gain the special barrier power from the first line, she still may place the 8 tokens from the second line.

Why can the same not be applied to Freeze/Ice Blast?

And again with the Ice Blast Ring

Is there an official ruling on that?

It appears that freeze should be able to barrier (power action), incap (free action), barrier (free action).

He can't gain the free action Barrier because he can already use Barrier. There is no entry on the official site, so post it up or I'll do it later when I get home.

I already asked but they haven't answered yet.

And now that I checked my E-mail to see if they disapproved the post yet, I see that they disapproved my question about Mera because the set isn't released yet (so they might not post this one either).
What irks me the most about any disapproval is that they never tell you what your question was... if you don't keep track of it yourself, you'll never know what they're replying to short of the title of the E-mail. :-s The least they could do is copy/paste your question in these situations so you could at least copy/paste the question later when the set is released. Ugh!

The additional free action "uses" barrier. The prior part where you gain it would be ignored because you already have it.

I also asked and have not heard back yet. I did get an official listing for X-23+Butcher though. I know a lot of people have been playing that wrong.