The concept seemed cool, but I couldn’t manage to play it. I tried connecting the arrows, but I don't understand why it wasn’t working. Really sorry about that.

Place tiles by selecting a tile on the bottom toolbar and then clicking somewhere on the grid. You can delete a tile by clicking on it and pressing delete or backspace. You can rotate tiles by pressing R before placing them on the grid.  All processing tiles (like muscles) must be placed on top of a straight blood vessel.