The cavity in photo 1 is the bottom edge of the hole for the rear of the extractor on 2nd generation P32s. It is a common occurrence on these Kel-Tec pistols. In it's self, it is not a problem. The burr that is left when the hole broke through the bottom of the slide is and is what caused the long scratch on the frame. I know that it is after the fact, but just sand/file/scrape (whatever works) the burr off the the slide. The scratch will not get any bigger and does not affect the functioning of the pistol. I just convinced myself it's a wear mark; if that helps.
The gouge in photo 3 is caused by the bottom of the extractor and is, again, a common occurrence. It happens at the furthest, rearward, movement of the slide; the damage is done, but, as you noted, has not affected (and probably will not) the pistol performance. Some folks file the bottom of the extractor to preclude the chance of more damage. I, personally, didn't want to screw with the extractor as it works flawlessly. I just filed the frame where it contacts the extractor to preclude said contact.
I have over 1000 rounds through my P32 (most after cleaning these areas up) and the gun has never missed a beat (knock on wood). That said, if the damaged areas bother you contact Kel-Tec about repair/replacement.
Regards,
Greg
BTW I imagine the scratch on the slide is caused by a burr created where the extractor hit the frame. That's purely speculation on my part as it didn't occur on mine.