Public Function SetRegValue(ByVal hKey As IntPtr, ByVal lpszSubKey As String, _
   ByVal sSetValue As String, _
   ByVal sValue As String, _
   Optional ByVal reg64 As Boolean = False, Optional ByVal reg32 As Boolean = False) As Boolean

    On Error GoTo ErrorRoutineErr

    Dim phkResult As IntPtr
    Dim lResult As Integer
    Dim SA As SECURITY_ATTRIBUTES
    Dim Create As Integer

    'Note: This function will create the key or
    'value if it doesn't exist.
    'Open or Create the key
    If reg64 Then
      RegCreateKeyEx(hKey, lpszSubKey, 0, vbNullString, _
       REG_OPTION_NON_VOLATILE, _
       KEY_ALL_ACCESS Or KEY_WOW64_64KEY, SA, phkResult, Create)
    ElseIf reg32 Then
      RegCreateKeyEx(hKey, lpszSubKey, 0, vbNullString, _
       REG_OPTION_NON_VOLATILE, _
       KEY_ALL_ACCESS Or KEY_WOW64_32KEY, SA, phkResult, Create)
    Else
      RegCreateKeyEx(hKey, lpszSubKey, 0, vbNullString, _
       REG_OPTION_NON_VOLATILE, _
       KEY_ALL_ACCESS, SA, phkResult, Create)
    End If

    lResult = RegSetValueEx(phkResult, sSetValue, 0, _
     REG_SZ, sValue, _
     (sValue.Length + 1) * 2)

    'Close the key
    RegCloseKey(phkResult)

    'Return SetRegValue Result
    SetRegValue = (lResult = ERROR_SUCCESS)
    Exit Function

ErrorRoutineErr:
    SetRegValue = False
  End Function

%ProgramFiles(x86)%\Proga\proga.exe

    SetRegValueExpandSZ(HKEY_CURRENT_USER, "Software\Test", "Test Value ExpandSZ 64", "%ProgramFiles%", True, False)
    '%ProgramFiles% 
    SetRegValue(HKEY_CURRENT_USER, "Software\Test", "Test Value SZ 64", "%ProgramFiles%", True, False)
    '%ProgramFiles% 
    SetRegValueExpandSZ(HKEY_CURRENT_USER, "Software\Test", "Test Value ExpandSZ 32", "%ProgramFiles%", False, True)
    '%ProgramFiles(x86)%
    SetRegValue(HKEY_CURRENT_USER, "Software\Test", "Test Value SZ 32", "%ProgramFiles%", False, True)
   '%ProgramFiles(x86)%
    SetRegValueExpandSZ(HKEY_CURRENT_USER, "Software\Test", "Test Value ExpandSZ NOFLAG", "%ProgramFiles%", False, False)
    '%ProgramFiles(x86)%
   SetRegValue(HKEY_CURRENT_USER, "Software\Test", "Test Value SZ NOFLAG", "%ProgramFiles%", False, False)
   '%ProgramFiles(x86)%

    '[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}\InprocServer32]
    If (sys_x64 = True) And (reg64 = False) Then 'мы на x64 OS и хотим писать в 32-битное представление
      'вместо этого мы пишем в 64-битном представлении, но явно указываем путь в WOW6432Node
      SetRegValue_ExpandSZ(HKEY_LOCAL_MACHINE, "SOFTWARE\WOW6432Node\Classes\CLSID\{XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}\InprocServer32", _
       "", "%ProgramFiles%\Proga\proga.dll", True, False)
    Else
      SetRegValue_ExpandSZ(HKEY_LOCAL_MACHINE, "SOFTWARE\Classes\CLSID\{XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}\InprocServer32", _
       "", "%ProgramFiles%\Proga\proga.dll", reg64, reg32)
    End If