In the step in tl-setup where you choose a password for tlwebadm it says "Please enter the desired password for this user, or leave unchanged to skip this step." If the user doesn't have a configured password and chooses to skip that step the tlwebaccess service doesn't start and the log says: 2014-05-05 14:41:05 ERROR tlwebadm[13117]: No password configured. Exiting. We should consider adding a warning in tl-setup indicating that no password is configured.
To clarify, it should still be possible to skip this step. tl-setup just needs to be more clear that doing so means that tlwebadm will be disabled.