Strange Error in Minkoff's SV Script...

Just recently I've begun to get a rather strange error in my game...

The line it refers to is this one:
 #--------------------------------------------------------------------------
  # * Obtain Pose
  #     pose_base   : default pose to return
  #     pose_actor  : list of poses for actors
  #     pose_enemy  : list of poses for enemies
  #--------------------------------------------------------------------------
  def pose_obtain(pose_base, pose_actor, pose_enemy)
    # create Arrays
    pos_a = {}
    pos_e = {}
    # fill created Arrays & Set pose
    pos_a = pose_actor
    pos_e = pose_enemy
    pose_now = pose_base
    # Obtain pose if not a standard pose
    if @battler.is_a?(Game_Actor)
      pose_now = pos_a[@battler.id] if pos_a[@battler.id] != nil
    else
      pose_now = pos_e[@battler.id] if pos_e[@battler.id] != nil
    end
    # Return the final pose (minus 1 for neceties)
 (THIS ONE:)-->pose_now -= 1 if pose_now != nil
    return pose_now
  end
It came with this script by Charlie Lee (I'm using all script found in the demo but I'm unsure whether I'm using v.6 or v.7; I don't have drain or demi in my game:
http://www.hbgames.org/forums/index.php?topic=28837.0
I'm also using these scripts
http://rmrk.net/index.php/topic,21396.0.html<--By NAMKCOR
And ccoa's UMS, but I don't know where I found it >_<. Sorry.
Can anyone help?

I don't know anything about scripting, but through general theory you should make 2 back ups of your game.

Open one of the backups and change the - inbetween pose_now and = to a !

And another just take out the - inbetween pose_now and =.

Don't do this with your main copy because I don't want to be the one who destroyed your RPG. ;o;

Tried both to no avail.
Both times both of the sprites froze, and when I executed an action the poses were delayed.
I think GMTBB is screwed >_<. I think I might copy/paste all my events onto a new game.
(Still swears loudly, though)

Can you upload another pic of the error? :x