Colin
How annoying for you, you didn't say whether this was a problem from boat delivery or not but it's sorted now. From my experience, part from forgetfullness to ensure the rudder was fully lowered and shallow water where the rudder " kicked up" i stll found the horizontall rudder gives some bite and steerage, not perfect but it still gave some steerage in the conditions at the time of my sailing. A usefull posting all the same to remind us how the lines should be routed.
Thanks
Peter