@Inca: I just reread that section and it appears to be largely the same as it was in 4th edition. The way it reads to me is that if I were casting Increase Agility on someone that had natural agility 3 plus two points of muscle toner, I'd need to cast it at force 5. Since the maximum any attribute can be increased is +4, I could only improve it to a total of 7. Basically what I'm getting from the book is that I need to cast at force equal to or greater than the augmented attribute at its pre-casting value, not its final value.
You're right on the calculation on spirits, I should have gotten three services, not four. How does the limit[Force] get applied to the opposed test? does it affect the net hits or the hits used during the test? AKA, if I summoned a F3 spirit and I got four hits and the spirit got just one, would I have three services or two?