I want to play Ark, I bought it and want to download it. But. Garry's Mod is doing a download. But the Garry's Mod download will not start at all. If I press resume, it will say it's doing it but not doing anything at all. Is there a way to switch my Ark download from the Steam? So I can have Ark downloading instead of the stupid broken Garry's mod one. Without deleting any of my game data?
You can re-arrange queue of download, and cancel the update/download of Gmod. You can do this by right-clicking on any game that is downloading, then clicking Manage Downloads. An alternative way of accessing Download manager is clicking the Downloading sign on the bottom of the Library section.
You will see Gmod downloading on the top. Click the pause button. Then click the up-arrow on Ark below to initiate downloading.
If I wanted to pause Starbound, and update Unturned, I would click pause on top-right and then the up-arrow on unturned to start the download.