Masterworking is a total fail?!

That means that it was +3 BEFORE you upgraded. Problem solved. Is your +4 ranks to hammer of the ancient a greater afix? If not, then +4 is totally correct.

I didn’t get this part. 25% of 40 is 10, so it should be +50 life per hit now.
Edit: Ah, ok I see, you didn’t hit for 25% yet.