hey, fairy! :--)

i would feed him in it, with the door SHUT - to get him accustomed to the idea while he is busy with something other than fretting over the door. he should be eating 2x each day, so that is 5 to 10-mins, twice daily. when he has finished his meal, do not wait for him to begin fussing; walk over, have a TREAT in Ur hand, lure him into a Down by holding it all the way at the bottom of the door till he lies-down to reach it, then when he drops on his elbows, praise him, feed the treat, open the door WHILE he is down + calm... this is good practice, and 2 pieces of skinless chicken-breast or cubes of low-fat mozzarella are not going to create a blimpoid puppy! i am speaking of 1/4 inch cubes or even 1/8th inch cubes - if he will drop for a 1/8th inch cube, then it works! ;--) why add more calories? he voted by offering wanted behavior... thats fine!

in addition, putting him in there with a good safe chew-toy * After * he has had a good romp + a potty-trip, to chew and nap, is a good idea - a safe chewy is 100% rubber + solid (a hefty bone-shape or an irregular ball like a molecular-model), a nylabone that is sized BIGGER than his current size - ex, if he is considered small get Med, if he is the wt of a Med-dog get a Lg, etc.
WASH any new chewy before giving it to the dog - rubber in particular has a powder on it to repel dirt, and believe me it tastes *awful* - i made a sandwich once after opening + handling a new rubber toy (without washing my hands, tsk!) and boy, was i sorry - yuk.

taking half his breakfast, adding a small amount of water (about 1 part h2o to 3 parts solids) letting it stand to soften, stuff it into a Kong (washed! :-) and freezing it overnight, creates a puppy pacifier - these are especially good when he hits 16-weeks and begins to drop teeth, the cold is soothing to lick + chew.
the BLACK Kongs are tougher, i would recommend that - and a Large one will fit him as an adult, no point in buying 2 sizes, he will outgrow puppyhood faster than U will believe, LOL. just fill the skinny end, do not stuff the entire Kong - about half the depth of the Kong is good.
Kongs are top-rack dishwasher safe for sanitizing, just soak the used Kong - i use an empty 32-oz yogurt container, plop in the Kong, cover w/ cold water, leave it on the counter out of reach of pets, or put it right in the DW to keep the kitty from getting into it; after the stuck bits soften, use a butterknife to gently scrape them off the walls, and put it wide-end down in the DW for cleaning.

i also put the crate within arms-reach of my bed, as any puppy under 16 to 20-weeks old goes out at 3-AM every night, till they can make it thru an 8-hour night without a pee break. take him out on-leash as late as possible, make sure he is empty, take him to the bedroom, close the door of the room, dress for bed, LAY OUT what U will need for the early-AM pee trip (coat, boots, whatever - be sure U have a TREAT for his voiding outdoors! put it in the pocket, or get it from the frig on the way out the door),
put the pup in the crate last thing; toss a goody in for him to follow, close the door, lights out, go to sleep.

IF * He * Fusses, and he just went in (he does not have an urgent need), BURP the crate - just a soft, firm thump with a flat palm on the roof of his shipping crate. the pup will be startled, this is more vibration than sound, he will FEEL it under his body. ** in that sudden pause / quiet, == praise the pup == warmly + quietly - 'Good boy, go to sleep...' or 'bedtime', or 'shhhhhh...' - something soothing + calm.
THEN - take a deep breath, Roll Over, and Sigh...
999 pups / dogs of 1,000 will do the same - get up or turn around,
settle comfortably, and go to sleep.

congratulations on the new pup! :--)
happy training,
--- terry

terry pride, APDT-Aus, apdt#1827, CVA, IPDTA, TDF