The generator matrix

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

generates a code of length 18 over Z2[X]/(X^2) who´s minimum homogenous weight is 17.

Homogenous weight enumerator: w(x)=1x^0+8x^17+10x^18+8x^19+2x^20+2x^22+1x^24

The gray image is a linear code over GF(2) with n=36, k=5 and d=17.
As d=17 is an upper bound for linear (36,5,2)-codes, this code is optimal over Z2[X]/(X^2) for dimension 5.
This code was found by Heurico 1.16 in 0.00077 seconds.