On those other two points, I'd like to know the answer, too. I'm not sure if bruising on the "tips of the temporal lobes" (whatever that really means) is somehow significant as an indicator of something.
The only thing I know about blood after death is what you mentioned, that in livor mortis blanching behavior changes with time, which suggests a change in the blood. That's really all I know about that.
The problem for lay people, of course, is that a pathologist will note things that may be indicative of something but b/c he knows what he's doing he doesn't explain that in the autopsy. It's up to the reader to understand all that...
MSNBC SPECIAL TONIGHT
WHO KILLED JONBENET
Sunday 8/27/06
8:00pm central time (9:00pm eastern)
repeated again at 11:00pm central time (12:00am eastern)
and again at 3:00am central time (4:00am eastern) on Monday Morning
Here's a PDF document that discusses rigor mortis, postmortem lividity, and some other things to do with changes in the body after death. Some good info in there that I thought you might like.
http://www.dundee.ac.uk/forensicmedicine/notes/timedeath.pdf#search=%22postmortem%22