Hi Cheri,
I'm new here too, but I have purchased both KPC and KM and was able to follow Cathe after just a few times through. I did take some kickboxing classes for about 6mo several years ago. It probably helped me in knowing the difference between a jab, hook, upper cut, etc. IMO, I think that you could catch on if you stick with it. I'm proof of that because when it comes to step I'm not as graceful and I can now complete Imax 2 successfully! Yeah! So if you're determined you could master all videos in question.
I do like KPC combo's better, but the leg drills at the end of KM are great addition to any leg work out or to any other work out. In fact, there's a thread already going on right now comparing the two. I think it was titled "How do you like Kickmax?".
Hope that helps. Welcome aboard, too! This place is addicting! Everyone is always so helpful (esp. with us newcomers)!
Dallas