I think it's because the installers of Legend of Grimrock has changed version. I deleted the download from the queue and started it again. It started from 0% again, even if the old file downloaded was still in the folder, so I discovered that the old chunks' name was setup_legend_of_grimrock_1.0.0.6.exe.n and now is setup_legend_of_grimrock_1.0.0.8.exe.n