Foulborn unique Kitava's thrist

I was just wondering if anyone else is having problems with the foulborn version of kitava's thirst. The problem is that when ever it spend the life cost of 00 or more it will not trigger any spells. I've tried with both blood magic and life tap support on different characters. Some please let me know if in setting it up wrong or is it working ass intended.

You need to spend the life on a single skill use, not combined cost of multible skill uses.