Unfortunately this behavior probably means that you made a typo in the fwkern.conf file. Traffic destined to the gateway itself (like SSH management) is never accelerated by SecureXL, and therefore is not subject to NAT Templates. Why did you enable NAT Templates in the first place? As mentioned in my book there are fairly limited scenarios where NAT Templates will boost performance, and the fact that they can only be enabled/disabled via a fwkern.conf modification and reboot is a bit unnerving.
--
Second Edition of my "Max Power" Firewall Book
Now Available at http://www.maxpowerfirewalls.com
Gateway Performance Optimization R81.20 Course
now available at maxpowerfirewalls.com