Well good luck with yours, I'm sure they'll fix it for you, Kimber would not be where it's at if they didn't make a good product, everything manufactured gets a glitch once in a while.
I've got a dime sized burn above my eyebrow from a Les Baer that liked to land them right on my head. Unforutnately settling on top of my glasses on occasion. Let's hope ejector filing if the answer to our prayers.
Removal of the external extractor isn't really difficult...
Depressing the firing pin safety (FPS), and firing pin allows the firing pin stop to come down and off the rear of the slide. This frees the firing pin and spring to be removed out the rear of the slide AND ALSO frees the rear extractor "plug" and spring to be removed from the rear of the slide.
Once they are out, that frees the front extractor plunger and extractor to be removed from the ejection port. Just rotate the tip of the extractor out and lift it free of its recess, then slide the front plunger out. Be careful to note the position of the front plunger as it has a flat on one side and must be reinstalled in the same orientation.
I don't know about spring life, but cleaning should be done at least every 1000 rounds, and I like every 500 better.