Send an email to BMW NA (bmwusa.com) and tell them that the pixels in your MID are out and are looking to see what they can do for you. After emailing them your info on their request, they will call you with one of two solutions: 1. Replace the MID at the dealership and cover 50% cost of the unit while you pay the other 50% plus labor (approx. one hour) or 2. Replace the MID at the dealership and cover 100% cost of the unit while you pay labor. They determine how much they cover on a case-by-case basis (don't know the criteria). The list for the unit is around $530 depending on the dealership. Trust me, your better off having BMW replace this thing instead of trying to take the thing apart and cleaning/fixing it yourself *guilty* I am in the process of having mine replaced right now. I called this morning to set up my appointment. They said the part would take 2-4 business days to come in. Good luck :)
The 8 Series has been out of production since the 1997, so getting BMw to pay for anything in 2013 is amazing. There was, however, a 15 year recall related to the headlights for adjustment as the mechanism itself can break; the headlights on some models also slid down when in the closed position, preventing them from popping up for use.
Regarding the pixels in the computer or radio - it's cheaper to replace the unit with a good used one; Pixels in the dash cluster require a new board. If considering a radio replacement, the CD43 Business Single CD is a direct fit and sells used on ebay for about $250.