There will not be much concrete/styrofoam/drain board exposed above the backfill and grading but the contractor doing the waterproofing has suggested the top outer layer be a different, exterior exposure type board than the drain board. Your point is well taken. 

Thanks for the input and diagrams Chris. There will be flashing over the top as your sketch shows.

One thing I always recall from the days when I worked in Europe much of the time is how the older, like centuries old, buildings, in many places are still in good shape at least where not damaged by wars.

I slept in a UK hotel near where the Magna Carta was signed. The hotel was built in the 1400's!  It struck me that one of the reasons their masonry/stone buildings last so long is that they don't have the extreme temperature swings that buildings in the US upper midwest do.

Thanks again.

Jim at Dawn