Upon replaying the tutorial, with the knowledge of being able to zoom in and out, I had no issues with seeing the blocks. However, even when zoomed in, the particles on the fans can be really hard to see still. Maybe my monitor just has bad color output though. As for the zoom in/out, since it didn't work outside welding mode, I never figured to try it when in welding mode. I think if you add a a blurb about it in the welding mode hint in the tutorial, it could clear things up better.