Just noticed that myself. I was testing with randseed:=1 just to see if i get same results with 1 thread or many. It crashed the moment i tried to set it on 1 thread Also 1 thread didn't result same kind of universe than 2 or more threads.
But that's fixed now. I added more debug info, like how many physics ticks are calculated, print out how many threads are used. Changed the visuals slightly, so that blue particles aren't add-blended, and there is the slow fade-to-black only when it is unpaused.
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