Use tracking with the Piwik API or query the Piwik MySql tables directly for the "breadcrumbs" of the skimmed traffic's actions.
I think you can install Piwik directly to a sub domain as a user on a server -- I wasn't root when I did the install -- I used in SSH with wget but you could do it the hard way in FTP also.
Piwik is simple PHP and JavaScript on your web pages (in the footer is recommended).
Fast start to the database for Piwik
piwik.schema.sql -- Database layout
Piwikfilter4.txt -- Sample JOIN query