Thanks for posting these errata. Helped me resolve some things. But I think you're wrong on Coral
Tunneling cost 5 pts per 1" of tunneling thru 1 DEF. Each additional 5pts adds 1" tunneling and 1 DEF. So 20 pts would be 4" tunneling thru DEF 4. Why do you think it should be 34 points?
For the HKA, "gradual effect" is a -1 limitation in 4th edition. It's -1/2 in 5th edition, but Coral is a 4th edition build. "Gradual effect" is not in the 4th edition rulebook, but you can find it in the 4th edition Hero Bestiary, p13, or 4th edition Fantasy Hero, p128. With a -1 limitation, the cost does come out to 34.
I agree the high point variant is incorrect.
