Optics Factory was great fun. In its best parts, it is probably my favourite 'factory' optimizer, but there were many points where the rules were quite nebulous. XRays, for example, were difficult enough to deal with being completely invisible, but also were not explained outside of a comment here to radiate out like a light source. Given the protrusion, I figured that it would just shoot out the front until I read the comment here. There were a few other aspects like that, but they were mostly negligible. During the game, I had found it quite slow, but I guess that was actually mostly on my computer because the lights were causing me so much lag that it took me two days with it on, but the game only registered 531 minutes of it. Given the lag, I had to build only one decent build per type of light and then delete it all and ride out that production to the next upgrade, so I don't even have a picture of my final build. However, the game was also very thematically on point, and quite original to boot so the game was overall quite refreshing.