The generator matrix

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

generates a code of length 21 over Z4[X]/(X^2+2,2X) who´s minimum homogenous weight is 14.

Homogenous weight enumerator: w(x)=1x^0+77x^14+193x^16+403x^18+256x^19+817x^20+512x^21+902x^22+256x^23+474x^24+138x^26+46x^28+13x^30+4x^32+3x^34+1x^36

The gray image is a code over GF(2) with n=84, k=12 and d=28.
This code was found by Heurico 1.16 in 0.326 seconds.