Error CS1061? Help me!!!

Hey guys, I am starting to get quite annoyed with my new project now as I recently downloaded the asset UnitZ (Unity Asset Store - The Best Assets for Game Making) although I keep getting an error that says- Assets/UnitZ/GUI/Elements/Common/PanelsManager.cs(135,42): error CS1061: Type UnityEngine.Animator’ does not contain a definition for isActiveAndEnabled' and no extension method isActiveAndEnabled’ of type UnityEngine.Animator' could be found (are you missing a using directive or an assembly reference?)
Here is the PanelsManager.cs script (PanelsManager.cs - Pastebin.com)
Do you guys have any ideas what is causing this problem / how to fix it? am a real unity noob btw and do not know any programming so and help would be greatly appreciated…

What happens if on line 135 you replace

if (anim && anim.isActiveAndEnabled) {

with just

if (anim) {

?