Tom Siemerink (www.f32.nl) sent me some good advice about handling the boat under power wich might be of interest for other builders.
I tried to translate it, but I'm not sure about the english nautical terms so I hope it's understandable.
Congratulations on the launching of your boat, it's looking good.
I'll give some unasked advice, hope you will benefit from it. We met a lot of the same problems.
To 'park' the boat we use at the bow and stern of the float a big round fender. This is the only way to avoid damage and it works really well.
Mostly it's better to dock backwards than going forward. With a lot of wind it is in any case difficult to dock on the windward side and difficult to get away from the side downwind.
You're right on your site: the boat is square and light and will drift quickly. On the downwind side we like to dock against another sailboat, because you can use the round shape of that boat to sail away (motor a bit forward while keeping the back docking lines attached and then motor away backwards, or the other way around). While docking it suffices to use one docking line on the middle of the float. When you fix this line first, the boat wil go nowehere and you've got plenty time to fasten the other docking lines. In the lock we only use this one middle line (now that's the good thing about owning a square boat).