The generator matrix

 1  0  1  1  1 X+2  1  1 X+2  1  1  0  1  1  2  1  1  X  1  1  X  1  1  2  1  1  0  1  1 X+2  1  1  1  1  0 X+2  1  1  1  1  1  1  1  1  2  X  2  X  X  X  0  X  X  2  X  X  0  X  X  2  1  1  1  1  1  1  1  1  1  1  1
 0  1 X+1 X+2  3  1  0 X+1  1 X+2  3  1  2 X+3  1  X  1  1  2 X+3  1  X  1  1  0 X+1  1 X+2  3  1  0 X+2 X+1  3  1  1  2  X X+3  1  2  X X+3  1  1  1  1  1  0 X+2  X  2  X  X  0 X+2  X  2  X  X  0  0  2  2 X+1 X+1 X+3 X+3 X+2 X+2  X
 0  0  2  2  0  2  2  0  0  0  2  2  2  2  2  0  0  0  0  0  2  2  2  0  0  0  2  2  2  0  2  0  2  0  0  2  2  0  2  0  0  2  0  2  2  0  0  2  2  2  2  2  2  2  0  0  0  0  0  0  0  2  2  0  0  2  2  0  0  2  2

generates a code of length 71 over Z4[X]/(X^2+2,2X) who´s minimum homogenous weight is 70.

Homogenous weight enumerator: w(x)=1x^0+12x^70+90x^71+13x^72+2x^74+4x^75+2x^76+1x^78+2x^79+1x^86

The gray image is a code over GF(2) with n=284, k=7 and d=140.
This code was found by Heurico 1.16 in 0.16 seconds.