I'm mostly done porting an old EV plug to EV Nova, and I have rediscovered a quirk that also existed in the original plug-in: every spöb created by the plug-in (not a total conversion) surrenders without sending its defense fleet. However, if you then release it and demand tribute again, the defense fleet appears.
I've tried creating new systems that reproduce existing ones (e.g. Sol) exactly, but the new planets also behave this way (and no, "planet is always dominated" is not set). Any thoughts on this?