The file conway_table.py.bz2 is used to generate the conway polynomial
database as follows:

 1) cd to SAGE_ROOT/data/conway_polynomials
 2) Delete the file conway_polynomials
 3) Make sure conway_table.py is not there and that 
    conway_table.py.bz2 is there (and has all relevant data)
 4) Start SAGE:
      sage: cp = ConwayPolynomials(read_only=False)
      sage: cp._init()
      sage: quit

Your data should now be in the database.