anchor.diff:      }
   }
   
  -Add-Type -Assembly System.Windows.Forms
   function Ask-Copy($src,$dst){
       $fname = (Join-Path $dst (Split-Path $src -Leaf))
       if( Test-Path $fname ){
  -        if( "Yes" -ne [System.Windows.Forms.MessageBox]::Show(
  -            'Override "{0}" by default ?' -f $fname,
  -            "NYAGOS Install", "YesNo","Question","button2") ){
  -            return
  -        }
  -    }
  -    Do-Copy $src $dst
  +        Write-Verbose "$fname already exists. Cancel to copy"
  +    }else{
  +        Do-Copy $src $dst
  +    }
   }
   
   function ForEach-GoDir{
  
positive.code:             $now = (Get-Date -Format "yyyyMMddHHmmss")
              try{
                  $old = (Join-Path $installDir "nyagos.exe")
                  Rename-Item -path $old -newname ($old + "-" + $now)
                  Do-Copy nyagos.exe $installDir
              }catch{
                  Write-Host "Could not update installed nyagos.exe"
                  Write-Host "Some processes holds nyagos.exe now"
              }
              # [void]([System.Windows.Forms.MessageBox]::Show("Done"))
              timeout /T 3
          }
      }
      "get" {
  
negative.code: function Do-Copy($src,$dst){
      Write-Verbose "$ copy '$src' '$dst'"
      Copy-Item $src $dst
  }
  
  function Do-Rename($old,$new){
      Write-Verbose "$ ren $old $new"
      Rename-Item -path $old -newname $new
  }
  
  function Do-Remove($file){
  