Hello,
You can add spell normally (just add "Crusader Strike" and WRobot will launch this spell when you select an enemy in range)
Or if you want automatically attack near enemy, in the spell name put:
local name = GetSpellInfo(35395);
TargetNearestEnemy();
if UnitExists("target") and UnitIsEnemy("player","target") and IsSpellInRange(name, "target") then
CastSpellByName(name, "target");
end
TargetLastTarget();
In spell settings "Combat only" > False, "Not spell, is lua script" > true, "Timer" > 3000 (for test all 3 secondes).