A few days after trying this scenario solo for the first time I decided to try again. The models are still the same but I decided to use some unbased trees to thicken out the forest, along with the rules modification that the priority player no longer controls the Ringwraith; if the Good side wants to influence its movement, a hobbit has to successfully throw a stone.
(Click on any image to see an enlargement.)
The Ringwraith had nearly cleared the treeline by turn three, so Sam stopped to distract it by throwing a stone. Unfortunately, he rolled a '1', and even using his single Might point wasn't enough to force a "hit". So the Ringwraith remained undistracted for turn 4.
Sam tried to throw another stone and succeeded. Now he knows to aim for the rocks and not the soft pine needles. Meanwhile the other three hobbits take advantage of the Ringwraith's preoccupation to hurry as far as they can to the ferry without being spotted.
Sam risked one more turn of no movement to throw another rock, but then got nervous about being left too far behind. The Ringwraith was thus able to begin to move back to the edge of the forest.
The other hobbits swung south to remain unspotted.
With nowhere else to hide, the hobbits decided to dash for the ferry. The Ringwraith now has them in his sights!
Priority starts to matter now, and Evil wins. The Ringwraith charges towards the hobbits and succeeds in getting within magic range. Last time I decided that I was too stingy with the magic use, so this time I had the Ringwraith Compel Frodo with two dice. The roll was a '6' (the best result), and Frodo's hand started moving to the ring. Frodo decided to resist with only one Will point, and managed to roll the needed '6' without even using his special hobbits-resist-magic rule. With a start Frodo jerks his hand away from the ring and he, Merry, and Pippin, thumbing their noses at the Nazgul, run for the ferry.
Left behind, Sam decides to charge the Ringwraith and easily passes his courage check. Good ol' Sam. The goal was just to drain the Ringwraith of a Will point, but despite the -1 unarmed penalty, Sam wins the combat and miraculously goes on to roll the 6,5 needed to eliminate the Ringwraith!
"Any more of them Black Riders that you need me to take care of before I start fixin' dinner, Mr. Frodo?" Well, this is why we game, isn't? But I didn't go to all the trouble of writing this stuff down and taking photographs just to have it all invalidated by wacky luck. So I decided to pretend that although Sam won the battle, he did not succeed in inflicting a wound, and the game played on.
Good wins the important priority roll, and Sam decides to charge the Ringwraith to ensure that the others make it to the ferry. Sam passes his courage check yet again, and though the Ringwraith wins the combat it fails to wound. It's now down to 3 Will.
Good wins priority again, and Sam again charges. He passes his courage check and wins the combat but fails to wound.
Frodo, Merry, and Pippin board the ferry and, somewhat meanly given Sam's heroics, cast off without him.
Evil finally wins priority, but with the other hobbits safe there's nothing to do but charge Sam. With the cavalry bonuses, the Ringwraith wins and inflicts a wound on brave Sam. Neither of Sam's Fate points avail him, so now the both sides are down to a single wound remaining. The Ringwraith has but one Will left.
Evil wins priority, but Sam uses his Might to call a Heroic move and, surprise!, charges the Ringwraith. He again passes his courage test, and again wins the combat (that's three of four times, despite the -1 modifier!). Though he fails to inflict a wound, the Ringwraith no longer has any Will points and dissolves with a menacing shriek.
Sam bandages himself up. "Coming, Mr. Frodo!"
I'm more convinced than ever that the lone Ringwraith has virtually no chance to win this scenario (though a draw might be possible). However, a bunch of Ringwraiths might be interesting, so I'm curious to see how the Bree and Weathertop scenarios work out.