I like the game. Took me some time to figure out all the mechanics - what I only figured out at the very end was that you can replace machines. Wished I would have known that before.
A minor thing that could be improved: Add a 3rd color to the skill tree, so that it is easily visible what can be researched next.
Um... There are three colors in the skill tree. Red for what's not available, yellow for what you can research if you have the sp, and green for completed researches. No? If there's a bug in that please let me know. Also I do mention replacing machines in the help book, although it's not emphasized as much as it probably should have been.
