mapfix script errors

C:\Users\jotun>powershell.exe -ExecutionPolicy Unrestricted -File "C:\Apps\Minec
raft\mc-mapfix-master\mapfix_installer.ps1"


    Directory: C:\Users\jotun\AppData\Roaming\.minecraft\versions


Mode                LastWriteTime     Length Name
----                -------------     ------ ----
d----         9/29/2014   8:50 PM            1.8_mapfix
The term 'jar' is not recognized as the name of a cmdlet, function, script file
, or operable program. Check the spelling of the name, or if a path was include
d, verify that the path is correct and try again.
At C:\Apps\Minecraft\mc-mapfix-master\mapfix_installer.ps1:19 char:8
+     jar <<<<  xf $version".jar" $classfile
    + CategoryInfo          : ObjectNotFound: (jar:String) [], CommandNotFound
   Exception
    + FullyQualifiedErrorId : CommandNotFoundException

Exception calling "ReadAllBytes" with "1" argument(s): "Could not find file 'C:
\Users\jotun\AppData\Roaming\.minecraft\versions\1.8_mapfix\bue.class'."
At C:\Apps\Minecraft\mc-mapfix-master\mapfix_installer.ps1:20 char:44
+     $bytes = [System.IO.File]::ReadAllBytes <<<< ($env:APPDATA + "\.minecraft
\versions\" + $version + $postfix + "\" + $classfile);
    + CategoryInfo          : NotSpecified: (:) [], MethodInvocationException
    + FullyQualifiedErrorId : DotNetMethodException

Cannot index into a null array.
At C:\Apps\Minecraft\mc-mapfix-master\mapfix_installer.ps1:21 char:12
+     $bytes[ <<<< $offset] = $newvalue;
    + CategoryInfo          : InvalidOperation: (2339:Int32) [], RuntimeExcept
   ion
    + FullyQualifiedErrorId : NullArray

Exception calling "WriteAllBytes" with "2" argument(s): "Value cannot be null.
Parameter name: bytes"
At C:\Apps\Minecraft\mc-mapfix-master\mapfix_installer.ps1:22 char:36
+     [System.IO.File]::WriteAllBytes <<<< ($env:APPDATA + "\.minecraft\version
s\" + $version + $postfix + "\" + $classfile, $bytes);
    + CategoryInfo          : NotSpecified: (:) [], MethodInvocationException
    + FullyQualifiedErrorId : DotNetMethodException

The term 'jar' is not recognized as the name of a cmdlet, function, script file
, or operable program. Check the spelling of the name, or if a path was include
d, verify that the path is correct and try again.
At C:\Apps\Minecraft\mc-mapfix-master\mapfix_installer.ps1:24 char:8
+     jar <<<<  Muf $version$postfix".jar" $classfile
    + CategoryInfo          : ObjectNotFound: (jar:String) [], CommandNotFound
   Exception
    + FullyQualifiedErrorId : CommandNotFoundException

Remove-Item : Cannot find path 'C:\Users\jotun\AppData\Roaming\.minecraft\versi
ons\1.8_mapfix\bue.class' because it does not exist.
At C:\Apps\Minecraft\mc-mapfix-master\mapfix_installer.ps1:25 char:16
+     Remove-Item <<<<  $classfile
    + CategoryInfo          : ObjectNotFound: (C:\Users\jotun\...apfix\bue.cla
   ss:String) [Remove-Item], ItemNotFoundException
    + FullyQualifiedErrorId : PathNotFound,Microsoft.PowerShell.Commands.Remov
   eItemCommand

Done!
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