Sitecom WL-173 and Hardware Static Route

Nobody have this router?

I'm trying with no success to configure some static route and disable
NAT. But I didn't menage to turn off NAT. Sitecom manual simply state
that once that static routes are set NAT turns off, but maybe there is
something else.

Sitecom user support, BTW is not resonding to my mail, and Sitecom
phone support don't even know what a "static route" is :-(