The generator matrix

 1  0  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  0  1  1  1  1  2  1  1  1  1  1  1  1  1  1  2  1  1  1  1  1  1 2a  1  1  1  1  1  1  1  1 2a  1  1  1  1  1  1  1 2a^2+2a  1  1  1  1  1  1  1  1  1 2a^2+2a  1  1  1  2  1  1  1  0  1  1  1 2a+2  1  1 2a+2  1  1  1  1  1 2a^2+2a  1
 0  1  1  a 3a^2+2 2a^2+3a+1 a^2+3a a^2+3a+3 3a^2+2a+3  0 2a^2+3  a 3a^2+2 a^2+3a 3a^2+2a+3 2a^2+3a+1 a^2+3a+3  2  2 2a^2+2a 3a^2+3  1 3a^2+3 2a^2+2 2a^2+3a+3 2a^2+3  1 3a^2+1 3a^2+1 a^2+2a+1 3a^2+2a+2 a+2 2a^2+2a+3 a^2+a a^2+3a+1 2a^2+2a+3  1 a^2+a a+2 a^2+3a+1 2a^2+3a+3 3a^2+2a+2 3a^2+a  1 2a^2+a 3a^2 3a+1 a^2+a+3 a^2+3a+2 3a^2 2a^2+a+3 3a^2+3a+1  1 2a^2+3  a 2a^2+2a a^2+2a+2 3a+1 3a^2+a a^2+a+3  1 2a+3 2a^2+a+2 2a+3 2a^2+a 2a^2+2 a^2+2a+2 2a^2+a+3 a^2+3a+2 3a^2+3a+1  1 a^2+2a+1  1 2a^2+a+2 2a^2+2a 2a^2+3a+1 a^2+a+2 a^2+3a+3  1 2a^2+3a+3 3a^2+3a a^2+a+1  1 2a^2+a 2a^2+2a+3  1 a^2+a+3 3a^2+3a+2 a+1 2a+1 2a^2+a+2  1 2a^2+2a+1
 0  0 2a^2+2 2a  2  0 2a+2 2a^2+2a+2 2a^2+2a 2a^2 2a 2a^2+2a 2a+2  2 2a^2+2 2a^2+2a+2 2a^2 2a^2+2 2a^2+2a+2  2 2a^2 2a 2a 2a+2 2a^2+2a  0 2a+2 2a^2+2a+2 2a+2  0  0  2 2a^2+2a 2a^2+2a+2 2a+2  2 2a^2+2a+2 2a 2a+2 2a 2a^2 2a^2+2 2a^2+2a 2a^2  0 2a^2+2a  2 2a^2+2 2a^2 2a 2a^2+2  2  2 2a^2+2a+2 2a^2 2a^2+2a 2a^2 2a 2a^2+2  0 2a^2+2 2a+2 2a^2+2a+2  0 2a 2a 2a^2+2a+2 2a+2  0 2a^2+2a 2a^2+2a  2 2a^2 2a^2+2 2a^2+2a+2 2a  0  2 2a+2 2a+2  2  0 2a^2+2a+2 2a+2 2a^2+2 2a^2+2 2a+2 2a^2+2 2a^2+2  2  2 2a 2a^2+2a

generates a code of length 93 over GR(64,4) who´s minimum homogenous weight is 639.

Homogenous weight enumerator: w(x)=1x^0+3080x^639+1932x^640+6048x^644+4872x^647+2996x^648+2520x^655+686x^656+4704x^660+3864x^663+1988x^664+77x^672

The gray image is a code over GF(8) with n=744, k=5 and d=639.
This code was found by Heurico 1.16 in 87 seconds.