Rubin,
That threshold is only hourly, but one of the nice things about KSS is that it has a built in script engine. So you can use that, or even just use rules and filters if you don't have too many DevIces. I can help you with a script to set a per/device threshold if that's what you need. But I already have a script to alert you of a device that hasn't sent a message within your specified time-frame.
As to your second question, it's possible to script your logs into different files or even into SQL. But another great thing about KSS is that you don't have to. You can configure it to send different devices into different files, archive logs, and even log to an external SQL database or other ODBC database without having to parse the log or write any scripts.
Acy