jk8,
the consulate does not do any stamping. All u get is the sealed
packet(s) . If you had a valid H1 /H4 visa stamp in ur passport,
they write "CWOP <ur interview date> " on top of it - i assume
that this h1/h4 visa is no longer valid.
I came thru frankfurt and while boarding from there, when they
saw this they asked me show the sealed pkts - the pkt has
an attachment where ur name and A no. etc are there.
They just took a look at it and let us in. I did not go for
transit visas ( while going from US, since I had the valid
visa on pp , no trasit visas either - this is as per the german
consulate website)
hope this helps,
u_me