Thank you so much! A BP project worked just fine in b7 too, not being native aside. It’s actually surprisingly performant, and the M1X is rumoured to have 2xCPU and 2-4xCPU cores compared to this, could be quite a competent little dev laptop!
Weirdly, your version string is 5.1.0, so maybe there’s another Early Access coming soon? Or maybe a full release once that version is finalised. Out of curiosity, does deleting foliage still spazz out your screen?
I tried building it too, but it was clear that it was going to take hours at best, so I gave up shortly after. 8GB RAM probably didn’t help, pretty sure I ran out of mem with the IDE open as well 
Now, if only Epic committed to releasing ARM-native builds, that would make my decision of getting one super easy. My alternative is the desktop with 5800x/ 3080, which would be a better experience for sure, but I don’t particularly want to do side projects on the desk as well, feels like work.