Nexus 1 had a few bugs like that. Few and very far between, but they could on occasion be game-breaking.
I recall I got a similar bug, once. I uninstalled the game, and on a later occasion re-installed and nearly beat the game. I don't recall however how I got it to work, or if I installed on a new PC the second time over or anything.
Still, if anyone's interested in the original, I'd recommend it, and it's 10 euro's off steam atm.