The generator matrix

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

generates a code of length 21 over Z4[X]/(X^2+2,2X) who´s minimum homogenous weight is 15.

Homogenous weight enumerator: w(x)=1x^0+72x^15+219x^16+376x^17+576x^18+920x^19+1236x^20+1336x^21+1280x^22+984x^23+579x^24+328x^25+192x^26+72x^27+12x^28+8x^29+1x^40

The gray image is a code over GF(2) with n=84, k=13 and d=30.
This code was found by Heurico 1.16 in 0.76 seconds.