Function SelectFile(optional $InitialDir, $Filter)
  ; If $InitialDir is omitted, the dialog does NOT default to @scriptdir or the
  ; current working directory - it opens wherever the user last browsed to in
  ; ANY prior OpenFileDialog on this machine. Pass $InitialDir explicitly if
  ; starting location matters.
  Dim $objSHELLexec, $CMD, $objSHELL, $fh, $paramFile, $rc, $builtFilter

  $SelectFile = ""
  $paramFile = "%TEMP%\_selectfile_params.txt"

  ; $Filter accepts any bare extension - txt, pdf, exe, or whatever else - and
  ; gets built into a full "Label|*.ext" filter automatically, e.g. "txt"
  ; becomes "TXT files (*.txt)|*.txt". If the caller already passed a full
  ; filter string (detected by the presence of "|"), it's used exactly as
  ; given, untouched.
  If $Filter <> "" And InStr($Filter, "|") = 0
    If Left($Filter, 1) = "."
      $Filter = SubStr($Filter, 2)
    EndIf
    $builtFilter = UCase($Filter) + " files (*." + $Filter + ")|*." + $Filter
  Else
    $builtFilter = $Filter
  EndIf

  $fh = FreeFileHandle()
  $rc = Open($fh, $paramFile, 5)
  $rc = WriteLine($fh, $builtFilter + @CRLF)
  $rc = WriteLine($fh, $InitialDir + @CRLF)
  $rc = Close($fh)

  $CMD = 'powershell.exe -NoProfile -STA -Command "' +
         'Add-Type -AssemblyName System.Windows.Forms; ' +
         '$p = Get-Content ' + Chr(39) + $paramFile + Chr(39) + '; ' +
         '$f = New-Object System.Windows.Forms.OpenFileDialog; ' +
         'if ($p[0]) { $f.Filter = $p[0] }; ' +
         'if ($p[1]) { $f.InitialDirectory = $p[1] }; ' +
         'if ($f.ShowDialog() -eq [System.Windows.Forms.DialogResult]::OK) { $f.FileName }"'

  $objSHELL = CreateObject("WScript.Shell")
  $objSHELLexec = $objSHELL.Exec($CMD)

  If Not $objSHELLexec.StdOut.AtEndOfStream
    $SelectFile = $objSHELLexec.StdOut.ReadLine()
  EndIf

  Del $paramFile
EndFunction

Dim $reportPath, $installerPath, $logPath

$reportPath = SelectFile("C:\Reports", "pdf")
If $reportPath <> ""
  ? "Selected report: " + $reportPath
EndIf

$installerPath = SelectFile("C:\Downloads", "exe")
If $installerPath <> ""
  ? "Selected installer: " + $installerPath
EndIf

$logPath = SelectFile("C:\Logs", "txt")
If $logPath <> ""
  ? "Selected log file: " + $logPath
EndIf