I usually just write it out atlanelan, but as Eric suggests you can redirect any console output to a file as pointed out.
Since you have the necessary root tree you probably have the necessary service installed, but make sure it's there:
% sudo pacman -Ss boot-user-@ -66mod
Make sure it says [installed]. You wouldn't have that 'boot-user' tree if it wasn't but still. Make sure.
Then run AS USER OBLIVE:
oblive@ Ob66 ~ % 66-tree -cnE oblive
oblive@ Ob66 ~ % 66-enable dbus-session-@ oblive
This will create a user tree and enable the user dbus service for you to use X in conjunction with up to date display managers and desktop environments. This is only necessary for automated graphical environments as I mentioned earlier.
After doing this make sure that the tree was created and the service enabled on top of it by again issuing '66-info -T' AS USER OBLIVE.
It should print exactly what I posted earlier.
After that you can reboot and everything should work.
Please read the section "
X SESSION: How to configure with module service"
from this Obarun news article to understand this.
Best of luck!