Hello Farlan,
Not quite sure what is going on here, but just in case try to see if there is a region like this one in your problematic file
[MATH=eng]el(Sig.r,no_red,no_red):0[/MATH]
Giving the value to the matrix element on the lower-right corner only (say zero), then all elements of that matrix will be zero
[MATH=eng]Sig.r=mat(0,0,0,0,0,0,0,0,0,3,3)[/MATH]
By moving this region you might get zero values or non-zero values depending where the region was placed.
I might be wrong about all of this. In that case, please be more specific what is actually happening in your case.
Regards,
radovan
When Sisyphus climbed to the top of a hill, they said: "Wrong boulder!"