Hello Juan -
To the best of my knowledge and understanding, there are only 3 people certified by Ron to apply the groove in the world, and those are Ron himself, Tracy Galloway in Reno Nevada and Michael in Minnesota. You could become one yourself, as I believe still has sets of bits to gift to people who take the training.to become certified.
Filling the PCV valve is enough - I wouldn't advise filling the port on your intake, because reversing that is quite a chore.
new vehicle warranty - this is something to be mindful and cautious about. IF a major issue develops, and it is discovered by the people doing the warranty repair that you have modified the vehicle, they could make a case to the manufacturer to deny your warranty coverage. I would only advise grooving a vehicle once it is past any warranty period - which is usually where the manufacturer wants you to consider buying a new car. Choosing to put the groove on at that point should (and generally does) make it perform better than it did when it was new.
computer - You truly must think holistically about the car, just like the computer does for the manufacturer. We've been doing this long enough now to understand how the computer works and what it looks for from various sensors, namely the upstream oxygen sensor(s) and the MAP sensor (if your car has one, which most do these days), and we know how to modify the signal the computer sees after the groove has been added to keep it happy...and the cost of applying those fixes is quickly returned in fuel savings.
I hope this helps you solidify your commitment to modifying your vehicle with The Groove.