Factoricule

Listen, the controls are arcane, I'm sorry. If you can get past them, this game is very fun.

Hydrogen is green, Carbon is red, and Oxygen is blue.

It is WASD to move your character (the large dot)

VGBN + click to place conveyer belts (these are used to harvest resources too)

To build a assembler, first hold Q, and then hold E + click for ethanol, or O + click for Carbon dioxide, H + click for water, C+ click for citric acid, Y + click for Ethylene, and X + click for glucose. There is also the special 'Cup' assembler which simply checks your score, and is the victory condition. To build the cup, Hold Q, hold F and click. 

To place a mechanical arm, hold R + click. The arm has an input and output directions as indicated by the red and green lines at its base. Red is input, green is output. To adjust the angle of the input and output, use IJKL.  Once another structure is built (Arm, or assembler) the arm will no longer be adjustable. 

Assemblers make use of the resources inside of them to construct the molecule they make. For example a water assembler takes two hydrogen and one oxygen to make one water. 

Hydrogen + Carbon = Ethylene
Hydrogen + Oxygen = Water
Carbon + Oxygen = Carbon Dioxide
Ethylene + Carbon dioxide = Glucose
Ethylene + Water = Ethanol (alcohol )
Carbon Dioxide + Water = Citric Acid