Don't know if it's a bug, but I'm pretty sure the game is cheating me by just not spawning one of the ingredients I need to complete the game. I played like 5 times, only completed 1, the rest of the time one of the ingredients just didn't exist. One time I'm pretty sure it spawned an ingredient in a cabinet later into the round, I'd already checked everything over like 5 times and then suddenly it was there, but too late for me to win.
Also, even when it works, sometimes the RNG will just give you a bunch of formulas only using like 2 of the machines so the game just becomes a bunch of waiting and you have no way to improve your score. It's a cool concept but maybe needs more machine options and some safeguards against RNG that wrecks any chance to get a good score. If you had more machines and a bigger lab you could also have extra ingredients you don't need and decoy formulas that take you in the wrong direction, that would contribute some much needed gameplay variety.