Hmm, I'll start at the top :->. Well, first thing is that Kenmore doesn't manufacture any appliances. The only thing Sears has is the name recognition, therefore, they have GE, LG, Whirlpool, and others to make appliances for them and Kenmore slaps on their label.
On with the problems though :->
1. Door is grungy looking. Make sure your air-gap ( if you have one) is clear and not clogged. If you don't have one, make sure the drain hose is mounted to the underside of the counter, under the sink. This will prevent Gookus from backfilling into your dw.
2. There are 3 main things to check when repairing dw - Circulation, Heat, and Drainage. There's not much else. Here are some tips to address each one.
a) Make sure all spray arms are turning. Put in one position, close door, run, open, and verifiy they moved. If not, clean holes in spray arms, or, remove filter and clean around impeller or chopper. I find clogs all the time.
b) Heat. Make sure you are running your hot water in the sink until max hot water is reached. This is very important and should be listed in the users manual. Most dw's run several cycles before the heater element is energized. Water must be 120F when entering dw.
c) Hard Water buildup. Use Lemon Shine, available from Walmart. This will clean the dw and prevent buildup on dishes.
d) drainage. Addressed above. I've seen countless times where food and other gookus goes right down garbage disposal and into the dw drain line, where it recirculates on to dishes. Make sure air-gap is clear or that hose is secured to underside of countertop.
e) Make sure the element is working. Once easy way to check is to verify dishes are dry at the end of the cycle. If not, call a service tech and get fixed. I've found black mold (splatter) on inside of dishwasher due to heater element bad.
Hope this help!