The second bug involves the Wizard skill Magic Weapon. The tooltip says that the skill increases weapon damage by 10%, but in reality it is applied twice, increasing weapon damage by a total of 21%. I first noticed this when playing with the Familiar rune Sparkflint, which states that it increases damage by 12%, and actually does so. I couldn't figure out why Sparkflint was not increasing damage as much as an unruned Magic Weapon. I looked over the DPS calculations and it doesn't seem like weapon damage is multiplied by itself at any point, so I believe that this is a bug.
Base damage: http://i.imgur.com/UB0pM.jpg
With Magic Weapon (unruned): http://i.imgur.com/dTxOl.jpg