Don't use ailerons that close to the ground, unless your're using them to null out rudder induced roll. Never use ailerons to turn when you are that close to the ground, and flying that slow--you are asking for trouble--especially with that plane, those ailerons are VERY responsive. OK, off of that issue.
I would guess (assuming your tailwheel setup is ok) that after landing, you are still moving just fast enough that there is no pressure on your tailwheel--in other words, the tail wheel is still off the ground, at least a little. Add that to the fact that you don't have enough propwash to make the rudder very effective and you have a non-steerable aircraft. What I would suggest is what has already been suggested--decrease the idle on your engine so that the plane slows down more upon approach. Also, decrease the pitch of the prop. If you are running a .46, you might try a 12 X 4 prop (depending upon the engine, of course). This will give more breaking power, and is a great match for that plane. You don't want to fly the twist very fast anyway, or it will self-destruct on you! If a 12 X 4 prop is too much, then try a 11X5 or 11X6, but those are fairly fast props on a strong .46! The twist is a floater, that will land very slowly if you stay on top of it, but it will also break in half on any rough landing, so be careful!