Heh, well, I have no proper knownledge of the actual limitations, like how often you can call BP nodes so this all is highly experimental. To be honest, I was surprised that it even worked in the first place. Did you get the crash with draw debug trace setting on or without it? Because if it’s on, it’s almost expected to crash as some point. I kinda put that setting just to test it, but in real project you should do your own debug draws from tick instead.
I tried with that debug draw off, 16 substeps, max substep delta time at 0.005 (so set to calculate physics 200 times in a second) and maxFPS at 10. I couldn’t get it crash here. Can you tell where in the engine it crashed?