UE 4.21 game crashing [i7-11700K processor]

hey there,
I’m trying to run an UE 4.21 game[Hello Guest Prototype, pretty stable build] with the setup: i7-11700K ; GTX 1660Ti ; 16 GB RAM. it crashes on start, no window pops up at all. runs on elder pc/laptop, it’s not a steam game. files aren’t missing, I checked.
just learnt that 4.21 might have a processor incompatibility bug, how am I supposed to fix that?