I just put a almost new motor in my explorer, it is dripping oil from an area between the filter / motor and water is dripping around my driver side

I just put a motor in my suv not even a month ago, it is dripping oil & from around the
area between my oil filter and motor . oil and antifreeze are normal ! Every now and then
it will smoke when idle or when I sit at a light and first give it gas , not bad just for few
seconds.The people that put the motor in are telling me I need to have the motor
exchanged without them even looking at it ! Telling me it's burning the oil when I can see
it dripping off my frame. My motor is still under warranty so that not a issue , I just don't
want to pay the $400 to have someone switch it out if it's something else , or could
something on my engine be cracked where it would be leaking both but it not mixing
together . Also when I reve it up I hear a rattle/ clicking not from under the hood but
around the middle of the suv and it is hard to start sometimes. He is saying it the motor
but I think that might be my starter going out.