The generator matrix

 1  1  1  1  1  1  1
 0  2  0  0  2  2 2a
 0  0  2  0 2a^2+2 2a^2+2a+2 2a
 0  0  0  2  2 2a^2+2a 2a^2+2a

generates a code of length 7 over GR(64,4) who´s minimum homogenous weight is 32.

Homogenous weight enumerator: w(x)=1x^0+245x^32+588x^40+1666x^48+28672x^49+1596x^56

The gray image is a code over GF(8) with n=56, k=5 and d=32.
This code was found by Heurico 1.16 in 0.0197 seconds.