I have mixed feeling about this game. It's quite complex for a game made in three hours, but two factors reduce the fun aspect for me: first the fact that time runs from the beginning, so there's not much planning before everything rolls, opposed to the likes of, for example, Spacechem or Infinifactory which I adore. Second the level design, or the lack of. It seems to be pure random, and though I haven't looked into it very much, it seems for some levels you are not able to fulfil all three desired outputs because you'd have to cross belts (or change them on the run which to me feels a bit like cheating).
I prefer an approach with more planning beforehand and then sitting back and watch how your plan unfolds - or not! Which is part of the fun and challenge. You could easily add some constraints to where the different elements can be placed by the level generator to ensure each level can be completed "perfectly".
The graphics are not very intuitive, so some more detailed explanation on the game's page would help very much. Took me some time to figure out the output symbols' arrows are arrows and not part of the product I had to deliver, so I was clueless how I should form those lumps into the more sophisticated shapes.
If you'd rule out those complaints I have I guess I'd enjoy it a lot more!