Bug#532731: kalarm: crashes on desktop startup
This bug report is the same as the KDE bug report
It is almost certainly due to KAlarm trying to redisplay an alarm which
has a sound file associated. It's unlikely to be related to which window
manager is being used.
Can the reporter please go to the KDE bug report and attach to it the file
~/.kde/share/apps/kalarm/displaying.ics. This may help to track this one
down. After that, deleting the file should fix the problem at least
KAlarm author & maintainer.