Hi all - I have a series of questions related to plumbing as result of
getting involved with the rennovations the girlfriend is undertaking.
I recently relocated a laundry room to the basement from the main
floor with the help of the group (thank you).

1. As part of the reno she is redoing the kitchen which involes
relocating the sink and the dishwasher.

I now have the upstairs opened up to see what appears to me to be a
rather convoluted way of running the plumbing. But I am not a plumber
and maybe it has a very good reason for being that way - or maybe
not. Before proceeding to basically relocating what is there, I
thought I'd better find out if it is correct in the first place!

Here is a diagram at: http://www3.sympatico.ca/cill/plumb.jpg

2. To relocate the kitchen sink, the water pipes and drain are smack
dab behind a pile of air conditioning/forced air heating venting in
the basement. Rather than try to adjust copper piping back there, I
saw recently on a home show that people are using flexible plastic
piping for water these days? If so, can it be mated to existing
copper, is it 'durable' , and do they happen to make some flex
equivalent for drain piping? Does anyone have any experieince good or
bad with it?

3. The microwave is an over-the-stove type that acts a vent for an
electric stove beneath it. It has to be moved a few feet over and of
course that effects the venting. To my great dismay, I found out that
the venting just drops down between the walls and vents into the
basement. To me, this seems a no-no.

So - I also assume that it would not be a good idea to vent it into
the vent stack, but maybe try to run a separate vent ouside either
thru the basement wall below, or up thru the roof beside the existing
plumbing vent.

I apologize if these are rather inexperienced questions, but I would
rather appear stupid in advance of doing all of this as opposed to
after the fact. (or maybe both! lol)

TIA for any and all advice...