Ok look at these... This is a 100% het pied with markers & a ringer.
http://184.72.239.143/mu/a6898d77-c484-90ec.jpg
This is a 100% het pied with weak markers..
http://184.72.239.143/mu/a6898d77-c4bc-9834.jpg
And this is NOT het for anything but it has the same markers..
http://184.72.239.143/mu/a6898d77-c50c-e9a5.jpg
Some people have said in the past that the thicker they are and if they curve into the vent area that they are more likely to be het but this is simply not true.
Then there is the OPs question about the spot. Look at this pic. That white spot outlined in orange in not a ringer or a het marker. It's a very common pattern spot that many normals and morphs alike can have.
http://184.72.239.143/mu/a6898d77-c668-16d3.jpg
So once again, if the snake was sold to you or the person you got it from as a 100% het then it is het. Otherwise it is not unless it happens to be a wild caught or captive hatched African ball. In that case some people may want to breed it to a pied to see if it's het but a white spot is never a marker. Only RR tracks and ringers but only if the snake is already known to be het. Otherwise it is simply a pattern.