Ubisoft has released a patch to remove the always-on DRM from the PC version of From Dust. According to the Steam notes, installing the patch will result in the title being playable offline, and move the game save file from Ubisoft's server to your PC.
From Dust was originally expected to require a one-off online activation but released with always-on DRM, a "misunderstanding" Ubisoftapologised for last month.