Hi,
Craig asked and I tried to respond about Squeak on High Sierra. The email was rejected, so, 2nd try.
I don't build but do happily run Squeak on High Sierra. It runs fine on both HFS+ and APFS disks without any difficulties. I do use recent VMs and the two I've used recently are cog_macos64x64_squeak.cog.spur_201706080104.tar.gz and cog_macos64x64_squeak.cog.spur_201710261813.tar.
cheers
bruce