Further to address the OP’s request for info on makeshift materials, impersonations, etc.:
Colditz Castle in Saxony, Germay was home to a special “punishment” camp for officers; here were sent those who had attempted escape multiple times, or whose dossiers were marked as “anti-German.” The Germans developed this Sonderlager on the principle of putting all the rotten eggs in one basket. In fact, despite being a stone 16th century fortress built on solid rock, the POWs managed to stage numerous ingenious escapes, including a tunnel that started in a clock tower, impersonation of a particularly well-known German guard Sergeant-Major, and of course, building the famous glider (which was never used for escape, the war ending before an opportunity presented itself). The Polish officers at Colditz (who were the first POWs moved to the castle) had already managed to lockpick most of the rooms, and had produced their own keys for many doors by the time the first British POWs arrived.
Some of the most remarkable items produced by the POWs in Colditz include:
A fully operational typewriter made of wood (for producing fake documents); a sewing-machine made of wood (for producing fake German uniforms–photo on the same page as the typewriter), and fake official-looking rubberstamps, carved out of linoleum. These are remarkable works–they had to use the complex “Fraktur” typeface, and furthermore, had to be carved in reverse! I’ve seen the original stamps from Colditz (in the collection of the Imperial War Museum in London), as well as the original plans for the glider.
The Colditz glider, its builders, and a flying replica.
A list of the more remarkable escape attempts from Colditz.
If you want the best reference on escape tactics, attempts, and the extremely clever ruses used by Allied POWs in Germany, you should seek out “Escape From Germany,” by Aiden Crawley (himself an ex-POW); this was originally an official report to the RAF, and was kept classified through the Cold War, as it was felt that the methods might still be of use.
Finally, an excellently-researched web page about the “Great Escape,” which addresses many of the queries in the OP, and has the bonus of following up the murder of the 50 escapers with the story of how the Gestapo thugs were themselves hunted down after the war.
