First use FileSize() to find the size of the file if it's not already known. Then subtract 127 from that to find the offset you need to seek to. Then after opening the file, use SeekStream() to position the file pointer.
Strict Local Size:int = FileSize("MyFile.dat") If Size >= 128 Local Input:TStream = ReadStream("MyFile.dat") SeekStream(Input,Size-127) ReadTheInfoFromFile() CloseStream Input End If