When you use the Ubuntu package manager to install Zoneminder on Ubuntu 14.04 using the PPA, one configuration line defaults to the wrong path. This prevents the web console from showing you videos or events, although if you configure a camera it will capture pictures from it correctly and show you them in the Zone editing tools.
Specifically, under Options->Paths you need to change PATH_ZMS to:
/zm/cgi-bin/nph-zms
(adding the /zm to the front).
Error log messages look like the following:
ERR [socket_sendto( /var/run/zm/zms-299592s.sock ) failed: No such file or directory]
One other issue that could cause similar behavior is not having mod-cgi enabled in apache.