Hi, so I purchased my rMPB literally the day it was introduced in mid 2012 but I've always had a few little problems with it. It arrived loaded with Lion but got the free upgrade to Mountain Lion; 1st problem - it just won't load Mountain Lion. It says it needs 5 days to download and then crashes at the last hour. 2nd problem; it won't load videos, especially youtube and when it does it forces a restart. 3rd problem; overheating. Even when I have safari with 2 tabs open with pages for my dissertation it makes a really loud noise and is super hot until I restart but then it just does it again Is this normal?