When I updated the Artificer template to 13.0.1 the frontend of the site is now having 500 error occur even when the theme is not set to the site default. Simply having it enabled will cause this to happen.
I have tried disabling / removing this theme and attempt to install it fresh, but regardless of how many attempts, doesn't seem to remedy the issue.
Figured out a current workaround from using the App Store as that always resulted in an install error it seems. Manually downloaded from the UNA site, unzipped and uploaded to the server, installed, works like a charm.