Unfortunately the game is too big for Single File download from Itch.io, which right now has the limit of 4gb per file, so it's impossible to use Itch.io app to download SCC from what I know. You will have to do it manually from any outside link above or you can download from itch.io but in 3 files (the file endings of .7z.001, .7z.002 and .7z.003 and then repacking them)
Sorry for the issue.