Is one who downloads a song or a series that contains words or scenes that violate Tawhid considered an infidel, knowing that the download is for another purpose, and what about publishing a clip accompanied by a song whose words are similar to the aforementioned, for admiration of the music without the words?

Merely downloading the film does not constitute disbelief (kufr) if the person does not approve of the disbelief contained within it, but it does not absolve him of sin. It is forbidden to publish anything that contains disbelief, and its publisher bears the sin of those who view it after publication, due to the Almighty's saying: "And they will surely carry their [own] burdens and other burdens along with their own burdens," and His saying: "That they may bear their own burdens in full on the Day of Resurrection, and some of the burdens of those whom they misguide without knowledge." And due to the Messenger of Allah (peace be upon him) saying: "And whoever calls to misguidance will have a sin upon him similar to the sins of those who follow him, without that diminishing anything from their sins."