Whenever I try to use lockpicking, the lock is simply invisible. I hear rattling as I move my mouse or press A/W to try to actually pick the lock; but it seems that no lock or lockpicking overlay is displayed.

All I see as I enter lockpicking mode is "blurred everything around me" in background which, I suppose, should actually be a background to the lock.

But there's no lock. No lockpicks, or bobby pin. They simply aren't displayed.

Tech specs:

ATI Radeon 7200 series with up-to-date drivers (just checked)

Intel core i3 4160 4CPU 3.6 GHz

Win 8.1

Same bug persisted in standard (pre-set by autodetect) 800x600 fullscreen mode AND in 1280x1024 borderless windowed mode.

Yep this is a known bug. Check out the report index