Actually no, I hadn't used any mods. I got some replies over on my Mantis post, and it seems to be limited to Mac users running the latest version of MacOS (El Capitan).

I've submitted this on Mantis as well. If anyone has any suggestions, let me know

Hello! This is my first post, so hopefully I've put it in the right place. I have played this game throughout the Alpha, but this is the first time I've loaded it since it officially launched. When I loaded it up, the trees, and any objects (workers, the workers' bus, etc) are rendering as red boxes...