Why can't I change this

Private Sub InitializeImages()
       Try
           imageDictionary("picBlock1") = Image.FromFile(Path.Combine(ImagesFolder, "Block.png"))
           imageDictionary("picBaddy1") = Image.FromFile(Path.Combine(ImagesFolder, "Baddy 1 anim.gif"))
           imageDictionary("picBaddy2") = Image.FromFile(Path.Combine(ImagesFolder, "Baddy 2 anim.gif"))
           imageDictionary("picBaddy3") = Image.FromFile(Path.Combine(ImagesFolder, "Baddy3.gif"))
           imageDictionary("picBaddy4") = Image.FromFile(Path.Combine(ImagesFolder, "Baddy4.gif"))
           imageDictionary("picBall") = Image.FromFile(Path.Combine(ImagesFolder, "Ball.gif"))
           imageDictionary("picBlockSwitch") = Image.FromFile(Path.Combine(ImagesFolder, "BlockSwitch.png"))
           imageDictionary("picBomb") = Image.FromFile(Path.Combine(ImagesFolder, "Bomb.gif"))
           imageDictionary("picCoin") = Image.FromFile(Path.Combine(ImagesFolder, "Coin.gif"))
           imageDictionary("picFinish") = Image.FromFile(Path.Combine(ImagesFolder, "Finish.gif"))
           imageDictionary("picFlipper1") = Image.FromFile(Path.Combine(ImagesFolder, "Flipper1.gif"))
           imageDictionary("picFlipper2") = Image.FromFile(Path.Combine(ImagesFolder, "Flipper2.gif"))
           imageDictionary("picFlipper3") = Image.FromFile(Path.Combine(ImagesFolder, "Flipper3.gif"))
           imageDictionary("picFlipper4") = Image.FromFile(Path.Combine(ImagesFolder, "Flipper4.gif"))
           imageDictionary("picGate") = Image.FromFile(Path.Combine(ImagesFolder, "Gate.gif"))
           imageDictionary("picKey") = Image.FromFile(Path.Combine(ImagesFolder, "Key.gif"))
           imageDictionary("picLazer1") = Image.FromFile(Path.Combine(ImagesFolder, "Lazer1.gif"))
           imageDictionary("picLazer2") = Image.FromFile(Path.Combine(ImagesFolder, "Lazer2.gif"))
           imageDictionary("picWarp") = Image.FromFile(Path.Combine(ImagesFolder, "Warp.gif"))
           imageDictionary("picWarp2") = Image.FromFile(Path.Combine(ImagesFolder, "Warp2.gif"))
           imageDictionary("picStart") = Image.FromFile(Path.Combine(ImagesFolder, "Guy.gif"))
           imageDictionary("picBlockStopper1") = Image.FromFile(Path.Combine(ImagesFolder, "Debris1.png"))
           ' Add other images similarly...

           ' List of image keys that are animated
           Dim animatedImageKeys As String() = {
               "picBaddy1", "picBaddy2", "picBaddy3", "picBaddy4",
               "picLazer1", "picLazer2", "picFlipper1", "picFlipper2",
               "picFlipper3", "picFlipper4", "picCoin", "picGate",
               "picKey", "picFinish", "picBall", "picBomb",
               "picWarp", "picWarp2", "picStart"
           }
            ' Add images that require animation to the animatedImages list
            For Each imgKey In animatedImageKeys
                If imageDictionary.ContainsKey(imgKey) Then
                    Dim img As Image = imageDictionary(imgKey)
                    animatedImages.Add(img)
                    ImageAnimator.Animate(img, AddressOf OnFrameChanged)
                End If
            Next
        Catch ex As Exception
            MessageBox.Show("Error loading images: " & ex.Message)
        End Try
    End Sub

To this

  Private Sub InitializeImages()
      Try
          imageDictionary("Block") = Image.FromFile(Path.Combine(ImagesFolder, "Block.png"))
          imageDictionary("Baddy1") = Image.FromFile(Path.Combine(ImagesFolder, "Baddy 1 anim.gif"))
          imageDictionary("Baddy2") = Image.FromFile(Path.Combine(ImagesFolder, "Baddy 2 anim.gif"))
          imageDictionary("Baddy3") = Image.FromFile(Path.Combine(ImagesFolder, "Baddy3.gif"))
          imageDictionary("Baddy4") = Image.FromFile(Path.Combine(ImagesFolder, "Baddy4.gif"))
          imageDictionary("Ball") = Image.FromFile(Path.Combine(ImagesFolder, "Ball.gif"))
          imageDictionary("BlockSwitch") = Image.FromFile(Path.Combine(ImagesFolder, "BlockSwitch.png"))
          imageDictionary("Bomb") = Image.FromFile(Path.Combine(ImagesFolder, "Bomb.gif"))
          imageDictionary("Coin") = Image.FromFile(Path.Combine(ImagesFolder, "Coin.gif"))
          imageDictionary("Finish") = Image.FromFile(Path.Combine(ImagesFolder, "Finish.gif"))
          imageDictionary("FlipperLeft") = Image.FromFile(Path.Combine(ImagesFolder, "Flipper1.gif"))
          imageDictionary("FlipperRight") = Image.FromFile(Path.Combine(ImagesFolder, "Flipper2.gif"))
          imageDictionary("FlipperUp") = Image.FromFile(Path.Combine(ImagesFolder, "Flipper3.gif"))
          imageDictionary("FlipperDown") = Image.FromFile(Path.Combine(ImagesFolder, "Flipper4.gif"))
          imageDictionary("Gate") = Image.FromFile(Path.Combine(ImagesFolder, "Gate.gif"))
          imageDictionary("Key") = Image.FromFile(Path.Combine(ImagesFolder, "Key.gif"))
          imageDictionary("LazerY") = Image.FromFile(Path.Combine(ImagesFolder, "Lazer1.gif"))
          imageDictionary("LazerX") = Image.FromFile(Path.Combine(ImagesFolder, "Lazer2.gif"))
          imageDictionary("Warp") = Image.FromFile(Path.Combine(ImagesFolder, "Warp.gif"))
          imageDictionary("Warp2") = Image.FromFile(Path.Combine(ImagesFolder, "Warp2.gif"))
          imageDictionary("Hero") = Image.FromFile(Path.Combine(ImagesFolder, "Guy.gif"))
          imageDictionary("BlockStopper") = Image.FromFile(Path.Combine(ImagesFolder, "Debris1.png"))
          ' Add other images similarly...

          ' List of image keys that are animated
          Dim animatedImageKeys As String() = {
              "Baddy1", "Baddy2", "Baddy3", "Baddy4",
              "LazerX", "LazerY", "FlipperLeft", "FlipperRight",
              "FlipperUp", "FlipperDown", "Coin", "Gate",
              "Key", "Finish", "Ball", "Bomb",
              "Warp", "Warp2", "picStart"
            }

            ' Add images that require animation to the animatedImages list
            For Each imgKey In animatedImageKeys
                If imageDictionary.ContainsKey(imgKey) Then
                    Dim img As Image = imageDictionary(imgKey)
                    animatedImages.Add(img)
                    ImageAnimator.Animate(img, AddressOf OnFrameChanged)
                End If
            Next
        Catch ex As Exception
            MessageBox.Show("Error loading images: " & ex.Message)
        End Try
    End Sub