Have a bit of advice for you...Try teaching the command "give" I tried this with my 11 week old boxer and she caught on very quickly....when he has something even something he should tell him "give it" you will probably need to lure him to do so...let him smell that tasty treat you have in your hand and tell him "give it" he will most likely give up whatever he has....once he has "given it" up treat him, praise him and give it back to him, that is why i recommend using first a chew toy or something that he is semi interested in...He will learn rather quickly that when someone takes something from him they are most likely going to give it back..Hence when he does have something in his mouth that you need him to give to you he will "give it"
The second piece of advice I have for you is it sounds like your little guy's favorite game is chase..Let that be a reward for him or a fun game, but make sure it has a cue use something like "i'm gonna get you" and begin the chase!! If he goes off and running without being invited to do so, you must not chase him!! Simply tell him "Too Bad" and go sit on the couch He will learn that chase is acceptable and fun only when he is inivted to play... I got all these tips from a book called "The Culture Clash" (Tulsa Dan's reccomendation) it is a really good book for anyone trying to train a dog now matter how young or old they are..
Trudy's Mom (aka Julie)
Trudy 10/30/01, Brindle, Black Mask, white paws, Natural ears