i'm not a expert by any means but I dont think it will be as easy as relacing drawer. - I reckon you would have to take it all apart and replace the housing as well, because on a autodose the only spray jets at the top of the housing will be in the middle compartment, on a manual dose the spray jets will be over the 3 compartments (prewash/rinse - normal does compartment and fabric softener compartment) and will switch to the required jets at the right time of the wash cycle .
The Autodose machine has only on water inlet solenoid where as a manual dose washing machine will have at least 2 water inlet solenoids inside (1 for soap detergent drawer and 1 for the fabric softener compartment)
If you put in a manual dose drawer the machine will report 'wash drawer open' and will bleep like mad (it might even stop the washer) because with an autodose drawer that will press on a switch in the detergent housing to tellthe machine that the compartment drawer is closed, you dont get that switch on a manual dose samsung washing machine - plus the software will all need changing because the autodose washing machine will think that the autodose drawer is in it, its will not be intelligent enough to know you have changed it to a drawer off a manual dose machine.
if you are having trouble with dosage you could try trial and error approach, using granules you toss into the drum before washing which has an extra perfume fragrance in them like Lenor unstoppables something like that.
If you think its under dosing on detergent try another time with some liquid capsules, toss it/them into the drum and put the clothes on top, or add washing powder instead of liquid into the middle compartment of the auto dose drawer and see how you get on with that , sometimes powder is better than liquid as its got bleach in with the powder along with other chemicals that liquid might not have, and will keep the internals of the washing machine (drum etc) cleaner than liquid which can end up gooey especially if you wash on a cooler wash temperature most of the time. - If you are on ecological wash detergent (because of saving the environment or some other reason) try doing a few washes with Biological liquid or powder which is good for breaking down stains and odours . and try and use hotter washes to kill bacteria, so say if your garment says it will wash at 60'c then use a wash like that, dont use 30c or cold wash. and if you are washing underwear, and heavily soiled garments and towels and bed sheets or any garments that smell then choose 60'c wash cycle if your items can take that temperature a long wash at 60'c breaks down the bacteria and stops odours.
if its under dose of fabric softener then after your wash you could try selecting 1 rinse on the display panel then wait for it to start filling with water, pause the cycle (or open the drawer) and pour a capful of fabric softener into the middle compartment of the auto-dose drawer. You could also try a capful of Dettol laundry antibac germ killing sanitizer instead of fabric softener, that has a nice fresh smell.
After washing dont shut your washing machine door fully, wipe the grey door rubber gasket dry with a dry cloth and leave the door ajar slightly to let air circulate in the drum to dry it out and stop smells, if allows you to then also open the autodose drawer so that can dry out to and air can circulate in that otherwise that can get mouldy and make the machine/washing smell. and dont forget to do the maintenance wash/drum clean when it tells you too without any clothes in the drum and no detergent or additives, just let it use fresh water and heat.
Hopefully after all this your clothes will smell a lot better after washing.
Good Luck.
