/var/log/syslog could be useful. It is a logfile from the standard installed simple-syslog-daemon. Better would be to install klogd and sysklogd from developer mode. Maybe klogd is enough and would be easier(no need to remove simple-syslog-daemon). But as you can't install on the mounted partition, they need to be extracted and I don't know if something like this is possible because of this aegis thing. Which also stopped me to work more with harmattan. Edit: Maybe open-mode kernel could be of help.