I figure out that some code didn't change for the new 5.1 patch.
WindWalker.cs---line 77
Code:
if (!Me.HasAura("Energizing Brew") && Me.CurrentEnergy <= Me.MaxEnergy - (EnergyPerSec * 4) && Helpers.Unit.HasMyAura(Me, "Tiger Power" [COLOR=#ff0000]3[/COLOR]) && Me.CurrentTarget.IsWithinMeleeRange)
if (Spell.CastSpell("Fists of Fury"))
You should delete the letter "3", or else, it wouldn't cast fists of fury anymore..