With the amount of people that have had or are still having this problem and all the different system specs they have posted it seems to be completely random and intermittent.
At the very worse that I ever had it happen to me personally there was not only the double cursor, but also my standard windows cursor as well. This makes me believe there is a coding error in the cursor selection coding. Since the UI is Dynamic in that it is always updating itself with all the relevant information needed for the HUD, it would stand to reason the coding error is somewhere linked between the cursor selection and the HUD interface coding. It may just be a piece of phantom coding that randomly interferes, or it may be a coding error between, the cursor coding, the HUD/UI coding, and the OS.
If they released the cursor so people could also use it for their default windows cursor it might actually help correct the problem for people suffering from the more severe cases of this bug.
But on several occasions I've had my cursor go into Multiplicity Mode where there would be several duplicates following the main one around.
I've been using an "acquired" larger gold cursor for quite some time now, cause the original one was just way to damn small for me to see...
(I figured my multiplicity problem was because of this, so I would just restart the game to fix it.)
I have noticed that since They added Their Official Larger cursor, the problem has gone away.