Hey mate, sorry for late answer. The issue you're telling about is most definitely related to KAS. I encountered it myself on my own Münar base and had the same reaction as you. What's happening is what you described - parts spawn below the ground and turns everything into firework (at least a bit entertaining?). The solution in your end is unfortunately to make your base somewhere else, which must be more flat. I chose a frozen lake on Minmus (not harder to get to as landings are way easier), and carefully placed one module at a time and saved furiously between trips. No issues encountered yet. I'm sorry about your base, but when you've made it once, it's much easier to do it again