Well, Bullet is quite young, and far from stable. There are lots of “experimental” features.
About compiling: I didn’t include the Bullet source code directly, but have been running the MSVC projects which come with Bullet. The output has been (1) executables for the demos, and (2) static libraries for the major Bullet components. When building libpandabullet I include the Bullet headers, and then link the shared library against the static Bullet libs. Should be possible to reproduce on Linux too.
About build system: I am playing around a bit with waf currently. Not really my favorite, and I still have to find out how to run interrogate & interrogate_module, but waf supports Python 3 (unlike SCons), and I will be moving to Python 3 for most of my work soon.
There is still a lot o do at work before the end of the year, but in January/February I will have more spare time to spend on this project.