Hey folks, over the weekend we pushed the first patch to the game. In the Options / Graphics menu, there is a new option there to enable/disable the hardware mouse cursor.
This has a few effects:
1) DISABLING it should fix the disappearing mouse cursor for some people when in full-screen mode. Without going into too many technical details, for whatever reason their graphics configuration was scaling the cursor too big which resulted in it disappearing.
2) the software mouse cursor (again: with the option disabled) does perform worse as it updates on every frame with the game, so, you'll notice the movement will not be as smooth. In addition, due to the way the software mouse cursor renderer works, the cursor will scale with the window size and be present in any screengrabs.
3) the game may take a performance hit from doing this. For most systems it should be negligible, but for those running the game on any sort of Intel integrated graphics, this may cause grief.
Generally the issue for which this fix was implemented has been occurring primarily on some AMD-based chips, and specifically in Windows Vista for some reason, though.