Hello there and thank you for your feedback.
I have tried Hellspawner out on 3 different computers and I agree there's an optimisation issue with different computers due to the engine being used on standard settings. After some tinkering with settings like turning off blood & particle effects Hellspawner usually runs a lot smoother. The Engine does have issues with having both on as standard and even when I was stress testing Hellspawner I noticed these issues myself.
I apologise for any inconvenience caused by technical issues that you may have experienced in your playthrough and I hope the settings advice helps a little.
I thank you for your patience and support of Hellspawner and I hope you enjoy the sequel later this year. :)