Well, this is why you aren't getting FSAA:
Originally posted by Lord Blackdrago
That should be, according to the docs, export __GL_FSAA_MODE=4
As for SBA and FW, what are these "weird errors" when you startx? It's hard to tell you what to try when we don't know the error message...
You may also want to look at /proc/driver/nvidia/agp/host-bridge and /proc/driver/nvidia/agp/card, to see what your hardware supports. If both files don't report that the features are supported, then it won't enable, and it is remotely possible that this is causing the driver to not load.
Also, which distro are you using?