What is list of faults with model RSH1 Have you got a similar problems?

I purchased a samsung american fridge freezer model RSHI DBBP
It never worked properly, from I purchased it, I did not complain as my father was dying of cancer, when i felt better i complained to them I was told it was a recall problem, a man called and replaced both motors, I noticed, the one for the freezer he had removed had a black burn mark along the length of it.
After fitting I had more problems
it now freezes all the food in the middle shelf of freezer covering all in long hair like frost plus ice inside the sealed food. I called them again and got nothing but ignorance from the repair man He did not check for problems, he just shook his head and left . I contacted samsung to be told I was to pay for a p.c.b. ( main control for the unit) but when I reminded them it had just happened since the repair, they said they will fix it free of charge. my problem with this is, the repair man did not check it he has just guessed the p.c.b is to blame all the previous problems with the fridge are still there, so the new motors did not fix them.
find list below
fridge rots food ....cheese and veg. go black in three four days
freezer door turns all food to mush and sticky liquid
freezer light goes of and on
freezer either freezes rock solid or soft
last edition after new motors fitted is......
freezer covers all food (in middle compartment only) in heavy ice / frost
plus since getting this item my electric trip constantly goes off
I am worried to learn than some fridges have exploded causing lots of damage, especially after seeing my old motor with black burn marks on it. very worried !!