The documentation of Eidolon is now divided in two parts: the user guide contains the required background and useful informations concerning PET and the way the Simulator works.
The second part is useful for developpers and contains a more detailed description of the sources. A second document is dedicated to the use of the GNU debugger GDB with Obj-C.
For compatibility problems have a look at the credits section.
Technical docs are in the Developer Notes section.