My character kept sliding a little when I used Get Axis and I wanted to use GetAxisRaw instead of GetKeyDown so that the user can use either the Arrow Keys or WASD.  
// (c) Copyright HutongGames, LLC 2010-2011. All rights reserved.
using UnityEngine;
namespace HutongGames.PlayMaker.Actions
{
    [ActionCategory(ActionCategory.Input)]
    [Tooltip("Gets the value of the specified Input AxisRaw and stores it in a Float Variable. See Unity Input Manager doc.")]
    public class GetAxisRaw : FsmStateAction
    {
        [RequiredField]
        public FsmString axisName;
        public FsmFloat multiplier;
        [RequiredField]
        [UIHint(UIHint.Variable)]
        public FsmFloat store;
        public bool everyFrame;
        public override void Reset()
        {
            axisName = "";
            multiplier = 1.0f;
            store = null;
            everyFrame = true;
        }
        public override void OnEnter()
        {
            DoGetAxis();
            if (!everyFrame)
            {
                Finish();
            }
        }
        public override void OnUpdate()
        {
            DoGetAxis();
        }
        void DoGetAxis()
        {
            var axisValue = Input.GetAxisRaw(axisName.Value);
            // if variable set to none, assume multiplier of 1
            if (!multiplier.IsNone)
            {
                axisValue *= multiplier.Value;
            }
            store.Value = axisValue;
        }
    }
}