There are two things at play with your simulation and why you are not getting results.
1) You have mixed up the directions that the lattice vectors A and C represent. You have set your origin to A-3 C-6 when it should be the other way around, A-6 C-3.
2) There appears to also be an unexpected result in the PWE solver when setting the origin when the position of the crystal is set using the expression fields. Go to your crystal properties and set the position using the offset fields not the expressions.
Making these two corrections will yield a result with the bandgap and the defect.