I'm a bit confused about the chart on page 563 of the PRGCR regarding the Invisibility Special Ability in Appendix 1. The text states that "there are a number of modifiers that can be applied to this DC if the invisible creature is moving or engaged in a noisy activity." Then follows the chart, which appears to list modifiers to the Perception DC. Is this referring to the DC 20 to know when an invisible creature is within 30 ft., or the check to pinpoint the creature? The text also states that the DC is at +20 to pinpoint an invisible creature; is this referring to any of the normal DCs listed under the Perception skill or the DC 20 to know an invisible creature is present, or both?
The numbers in the chart don't make sense if they are modifiers to a DC... the modifier for someone not moving is -40!!