You don't need this patch if you bought the game after November 28 2009.
Instructions for Mac and Linux users:
1) open Machinarium folder.
2) open folder 00 and rewrite all older files with the new ones from the patch.
IMPORTANT NOTE: don’ t replace the whole directory but open it and update the files manually.
level Waste Dump: fixed logo over game and possibly frozen game while interaction with the rat.
level Furnace Room: interaction with right-side controller is now possible only when really standing near by.
level Alley: fixed possible lost of barrel while stopping game during animation of pulling the barrel from the bar.
level Sewer Room: fixed one incorrect state of water pipes.
level Bar: it’s easier now to beat the “bar bot” in 5-in-a-row game after several looses.