Hi Taniwha,
I absolutely love this mod as it's allowed me to become fairly independent from Kerbin, but I'm having some problems with it that I can't figure out. When I finalize a build on Bop or Pol, the root part of the craft being built immediately explodes. After this, the craft being launched is supposedly detached from the parent ship, but is frozen and hovers in place. I am unable to release it from the parent launchpads UI. This issue doesn't occur on minmus or kerbin, only the Joolian moons, although I haven't tested it elsewhere. It also doesn't occur in orbit around the joolian moons. Only at very low altitudes. I haven't determined the exact altitude where it starts occurring. I uses 6.4x RSS and a dozen other mods, I'm not sure if that would affect it...
Thanks for this mod! It's truly a gem