Try mixing Eggs, they always work with my lab. And the suggestion above, that the dog will finally eat when he's hungry also works. I have tried both successfully with my dog. My lab is on RC Maxi Adult, and she has those phases when she doesn't eat the dog food readily... my first action is to wait, 2nd to hand feed her, or trying to feed her while playing with her... you know like tossing the food pellets around so that she chases them and eats them, and if that doesn't work too, I start adding a boiled egg, or bread or curd to her food. With eggs, not only does she finish the food in a minute, she also keeps licking the bowl for 10 minutes after she's done eating :). Other than this, she gets some thing other than her regular food during the day in form of treats, so that we don't bore her totally.
But if you give in to your dog's demands and give him home cooked food as soon as he skips a meal, he'll never get used to the dog food.