Ten minutes into playing the third level, my (flaky) net connection flaked out. Guess what?
"Connection lost. Please wait until connection is restored."
In the end I had to reboot my PC to re-establish the link to the router. Lost all my level progress.
Since then, when I run From Dust it wants me to create a new profile - has it deleted -all- my progress? Brilliant.
Anyway, I think it's important this is made clear: the DRM check DOES kick in during gameplay and won't let you play anymore unless you can re-establish your connection.
As swearing is not permitted on this forum, I have nothing further to add.