Without knowing what the macro FileSaveWord11 is it is difficult to comment, however the following will save an existing document as DOC format - however be aware that DOC foirmat is not fully compatible with some later elements of DOCX format.
Code:
Sub SaveAsDOC()
Dim sPath As String
ActiveDocument.Save
sPath = Replace(ActiveDocument.FullName, ".docx", ".doc")
ActiveDocument.SaveAs2 FileName:=sPath, FileFormat:=wdFormatDocument97
End Sub