Code:
[ 175.725] Segmentation fault at address 0x0
[ 175.726]
Fatal server error:
[ 175.726] Caught signal 11 (Segmentation fault). Server aborting
Was the system rebooted with aperture set to 2
before you attempted to start X?
If the answer is no, that was your problem.
If you are sure you had your /etc files configured correctly, consider a newer snapshot. At this moment, there is a June 18 snapshot that included a Xenocara fileset updates.