When building the XCode Homeworld project it hangs very early on (AIAttackMan.c) and so I have to force quit. What's wrong?
You've forgotten to install the SDL.framework so XCode is unable to find the SDL headers. Install the SDL.framework
into /Library/Frameworks. (Unless it has been corrected it is possible you may also have to fix some broken "Headers" symlinks within the framework itself too). It should work fine after that.
: the SDL Framework's "Headers" symlink problem is fixed in SDL 1.2.8.