The Linux build does not work out of the box since the .pck file is missing. However, it's possible to just download the Windows build, rename its .pck file from it to Umami_Linux.pck and then run it with the Linux executable. (A .pck file is the file containing the actual game files: scripts, assets, scenes etc if you don't specifically tell Godot to pack everything into the executable itself)
As for the game, I like the idea of shrinking parts of it. There's a good amount of potential there to go further, like reusing already built and shrunken machines in later levels. The game also looks really cute, great job on the artstyle! Some ideas for improvement: The belts could better indicate what direction they are facing, and a recipe book would be nice, sometimes I had to guess which ingredients create what end product.