moved everything out of my ~/.../cura folder, removed and re-installed, same thing. Went grepping system logs and found this:
system.log:Oct 19 11:13:42 Christophers-Mac-Pro com.apple.xpc.launchd[1] (com.apple.xpc.launchd.oneshot.0x10000017.Ultimaker-Cura[92138]): Service exited with abnormal code: 255
system.log:Oct 19 11:14:11 Christophers-Mac-Pro com.apple.xpc.launchd[1] (nl.ultimaker.cura.21460[92188]): Service exited with abnormal code: 255
system.log:Oct 19 11:14:22 Christophers-Mac-Pro com.apple.xpc.launchd[1] (nl.ultimaker.cura.21460[92199]): Service exited with abnormal code: 255
system.log:Oct 19 11:16:25 Christophers-Mac-Pro com.apple.xpc.launchd[1] (com.apple.xpc.launchd.oneshot.0x10000018.Ultimaker-Cura[92279]): Service exited with abnormal code: 255
system.log:Oct 19 11:32:45 Christophers-Mac-Pro com.apple.xpc.launchd[1] (com.apple.xpc.launchd.oneshot.0x1000001b.Ultimaker-Cura[93106]): Service exited with abnormal code: 255
system.log:Oct 19 11:35:16 Christophers-Mac-Pro com.apple.xpc.launchd[1] (com.apple.xpc.launchd.oneshot.0x1000001d.Ultimaker-Cura[93291]): Service exited with abnormal code: 255
system.log:Oct 19 11:40:07 Christophers-Mac-Pro com.apple.xpc.launchd[1] (com.apple.xpc.launchd.oneshot.0x1000001f.Ultimaker-Cura[93769]): Service exited with abnormal code: 255
system.log:Oct 19 14:18:55 Christophers-Mac-Pro com.apple.xpc.launchd[1] (nl.ultimaker.cura.21784[4036]): Service exited with abnormal code: 255
system.log:Oct 19 14:19:15 Christophers-Mac-Pro com.apple.xpc.launchd[1] (nl.ultimaker.cura.21784[4053]): Service exited with abnormal code: 255
system.log:Oct 19 14:24:38 Christophers-Mac-Pro com.apple.xpc.launchd[1] (com.apple.xpc.launchd.oneshot.0x10000021.Ultimaker-Cura[4415]): Service exited with abnormal code: 255
not sure what "oneshot" is but looks like its involved. Maybe? idk.
(if it matters this is a hackintosh posing as MacPro6,1 running Catalina)