When Sears sells a customer an appliance and if for some reason there is discoloration due to self clean oven on the top of stove they will not replace the stove even after just a few months it is considered cosmetic. It occurs when you use self clean, they know this is an issue, and you are forced to live with this ugly abuse looking appliance.
The manufacturer knows this is an issue as well but doesn't change the design or material.
I believe that the venting on the stove is not correct and should be changed. Here is a tip, if you find that Sears tech's will not tell you it is a design flaw and Sears won't change then have your local fire department come in and assess the unit and if they deem it a fire hazard, you have a case for any good lawyer or ground to have it exchanged.