Rod,
Sorry I can't supply the SG numbers

but I
can give you some information on those stamps:
1. November 1980. Scott # 2148, Michel 2565 depicting the small gauge railroad line between Bad Doberan and Kühlungsborn.

2. April 1967 Scott 905, Michel 1271. 7th Congress of the Socialist Unity Party of Germany.
3. These are "ZKD Officials" They aren't specifically listed in Scott but in Michel they are "Dienstmarken - C" Laufkontrollzettel des ZKD. (Literally "operation control" I call them "route tracking" stamps.) The ones you show are from 1963. That series had 15 stamps. The abbreviation in the upper left corner tells you where they are from:
Shl - Suhl, Michel 14
Gra - Gera, Michel 6
Rst - Rostok, Michel 13
Mbg - Magdeburg, Michel 10
Cbs - Cottbus, Michel 2
Pdm - Potsdam, Michel 12
4. November 1974 Souvenir sheet, Scott 1592, Michel 1991 -94. Young Pioneers
5. These are semi-postals, Scott B15 -16, Michel 248, 249. for the 1950 Leipzig Spring fair. Here's a little write-up from my album:

Hope this helps!
Dan
