No I wouldnt recommend any other fluids in the CVT transmission other than the CVT fluid.

No. The transmissions rarely leak. I have a 2008 Sentra with 100,000 miles. I do a simple drain and fill of the trans fluid every couple years now.
Remember too, that most of the early transmission failures are with the heavier Altima's and Rogue's. The older Sentra's were bad too. But the smaller Versa's do not strain the CVT and can run much, much longer.

I actually had a customer ruin a transmission using that stuff, DON'T DO IT, just live with it!

AT-205 is a "Re-Sealer"  IT probably could damage your transmission.

Always use manufacturer specific fluids, where possible.

If somethings isn't broken, it doesn't need to get fixed.

PS.
In this case, I guess, putting that stuff in a CVT transmission isn't the end of the world, but lets say you have a Volkswagen with a DSG and you pour that thing in.. that, that would be really bad. 

I would fairy dust and Nome wishes before I would waste cash on that stuff. 

Here is where the cvt issue is to begin with a cvt transmission only has one drum with a pair of clutches for the forward and the rest is done by two metal plates that are chain and the way it switches gears is the second plates goes higher and higher away from the other if one of the plates starts getting scratches on it you will start noticing weird shifting hesitation to switch gears or even slipping the reason that happens is because you may have incorrect fluid, old dirty fluid or a lot of build up. If you want to cvt to last as long as possible change its oil every 20-30k miles if the oil comes out black just put it back and add a for sale sign on the car before it stops moving for good moral of story is if you want it to last regularly change the oil (if its not black) and add the correct fluid