Update

service/radangel.service

 ExecStartPre=/bin/chmod o+r ${EVENT_FILE}
 ExecStartPre=/bin/chmod o+r ${STATS_FILE}
 
-WorkingDirectory=/opt/radangel
+WorkingDirectory=/tmp
 ExecStart=/usr/bin/radangel --verbose \
 	--event ${EVENT_FILE}              \
 	--stats ${STATS_FILE}