Viewing post in Syahata's bad day(v1.0.5) comments
Yes, you can only download content during your subscription. (;′⌒`)
You can get version 0.79 here.
【ゲーム】 【更新】シャハタ遭難の一日 (Beta ver0.79a) - JaShinn Game (JaShinn)の投稿|ファンティア[Fantia]
Or you can wait for future steam and DLsite versions to be released.