This function does not let you save the files using different names. You would have to rename the files afterwards (or use the native Attachments collection, which would let you provide the name to save each file as).
Use the RenameFile() function to rename a file. It returns a boolean if the rename works. Use it like this:
if RenameFile("c:transferoldname.htm", "C:transfernewname.htm") then MsgBox "File was renamed" end if
I hope this helps.