In the runes section of this site it says you can put a rune in each of your armor pieces, so 5 total. I'm pretty sure I couldn't put a major fury rune in my boots though, is it a bug or recent change?
Also I couldn't put a rune in a Captain's helm that already had the +1skill mod, fine, but does this mean you can't put any runes in the whole Ascalon set also?