Reseting did nothing, sadly. It's an asparagus staged rocket so I've been changing staging in VAB extensively as is. I'll try to comply with these guidelines as best I can... KSP Version: Steam. 32-bit as far as I know, although I'm on a 64-bit machine I was under the impression Steam automatically launched the 32-bit version. What Happens: Instead of firing all four Kerbodyne-sized decouplers which are grouped together in a single stage at once, they fire one at a time. I don't know how to replicate or work around. I can't seem to attach files, but here are some screenshots: