Thank you for the reply, I actually came up with my doubt after reading that, I still cannot find an answer to my question, If I set the parameters:
<krpano version="1.0.8.15" preview.type="grid(,40,40)"> </krpano>
I get a working xml file and I'm able to load a cube grid preview with 40 x 40 squares, this is what confuses me, because I just left the part where I should specify the type of grid (Cube or Sphere) in blank and it automatically called up a cube for the preview, and it didn't tell me there was any error. Now, If I try to apply the same logic to the next parameter, the xsteps, say, I write this:
<krpano version="1.0.8.15" preview.type="grid(cube,,40)"> </krpano>
I don't get a working .xml file.
If the same logic applied it would call for the defaul amout of xsteps, or so I think it should. I've tried to put "" and 'default' with no satisfactory results. Maybe there's just no way to skip a parameter setting it to default automatically. ¿Any ideas?