Water pump or not?

[wmassr53]

Hi, Last Fall my 2006 R53 with about 72k miles on it was leaving a small puddle of coolant under it. I also noticed sometimes with the heat on it would start to blow cool air into the cabin. We tried to see if it was definitely a water pump as I have read they are a common replacement item but could not definitely point the finger there. My local Mini dealer Service person said he would not necessarily bet it's the water pump, if it is the water pump it was about $1595 to replace the water pump there. I have bought the Pelican Mini Cooper book and watched videos including the great 100k service video on the Wheeler Dealer show and after all this I believe I can change a bunch of component at the same time and save a lot of money. Can anyone tell me if they think this sounds like a water pump failure, I would like to start the project when it warms up here in Western Massachusetts.
My second question involves the supercharger which I would like to change the oil in at the same time as the water pump project. Since I bought the car in 2016 whenever I really stepped on the gas a certain odor appears, is this normal? does it mean anything?
Thank you in advance for any light that can be shed on these two issues!