Piercing Spell issues

[Chronocide]

Doesn't seem to allow me to use the piercing spell metamagic on all the inflict spells.

Like it works on the Inflict Light Wounds, and Inflict Critical Wounds, but not on Inflict Serious or Inflict Moderate.

For the Mass Inflict Spells, doesn't work on Light, but does work on Moderate, Serious, and Critical.

Anyone else having issues with this feat?

Also the lore master doesn't count it for their requirements (that one might be intentional)