LEts see here..
#1 - N52 CR is 10.7:1
#2 - Cast Iron
#3 - I know they are fracture split, aluminum alloy of some kind or a mild steel like the cam shafts.
#4 - Never looked into that LOL
#5 - I cant find any specs on the breaking point of the bolts, I know they are fragile and single use, but they dont list the specs anywhere I can find showing there rated failure point.