I have a similar question but didn't want to start a new thread. This is what I have upcomming:

Dec 9- Switzerland
Dec 10-14 -Germany
Dec 15-22 - England
Then I fly from Heathrow-Frankfurt on the 22nd, overnight it at the airport hotel, then I fly FRA-IAH.

My question is, I leave the schengen zone going to england, but then have a flight to germany (onwards to the US).

Since im re-entering the schengen zone is that a problem? Will I need to do something for a multiple entry visa for this?

Since this is all within a 90 days, I'm fine right? My problem comes with the interpretation of entering and exiting the schengen countries, since I'm leaving them after 6 days, and re-entering for a day a week later.