Log files which KIWI Syslog generate is in text format. Is it possible to encrypte this file or change the format of log files some how?
What specific data are you concerned about in the log files? There is no way I am aware of currently, however, since this is on the file system there are other methods available to secure Windows files, see here for a blog post I did on a similar topic for our Serv-U product.
You can log to a local or remote database as well which among other things does change the file format and can provide some additional security.