If some documents come out inverted or too small, probably your spooler is not supplying an end of job indicator at the end of each file. (This commonly happens on small machines that don't have spoolers.) You can force Dvips to do this with the `-F' flag (or `F' config file option), but this generates files with a terminating binary character (control-D). You can also try using the `-s' flag (or `s' config file option) to enclose the entire job in a save/restore pair. See section Command-line options, and section Dvips configuration files.