Sun has just removed XSun from SXCE 118 for X86/64 chips, so no I don't believe anyone there work on it any more other then bug fixes for legacy.
Lets see if we can get Nvidia working properly with Xorg. What Nvidia driver did you download?
According to the drive selection page:
Putting in GeForce 7 series outputs to use:
Is this the driver you installed?
Have you tried different settings using Nvidias configuration utility "/usr/bin/nvidia-settings" ?