If th eproblem is the engagement into drive while really cold, you probably have gummy deposits on the various valve body parts. Do you know when the last fluid change was? If never, like most vehicles, that is probably the root of your problem. Try pulling the plug and getting the easy 3 quarts of tranny fluid out and replaced. If it is dark brown and smells like varnish, you have a problem. If dark brown and no bad smell, run it a couple of thousand miles and redo the 3 quart thing. Eventually you will end up with a tranny flush with the fluid looking ans smelling like it was fresh out of the can.