I've been slowly getting it back to a low brace (about 4") and pulled it back to about 35 pounds. As I said earlier, the two main problems are getting the draw weight down without running out of heart wood and keeping good string alignment despite the twist.
I've been working down the sapwood on the back to bring down the draw weight, I've been attacking it quite roughly with a coarse rasp, but taking care to keep it fairly even, then cleaning it up with a finer rasp.
Basically I'm decrowning it and then following round towards the edges of the bow following a ring or maybe one or two above the layer where it's decrowned. The finished effect will be one continuous ring meandering down the centre of the back with a few rings showing either side and then a continuous ring out twards the edge of the limb. I'll post a pic when it's finished so you can see what I mean.
I've also worked on narrowing/aligning the tip so it looks ok at about 15" of draw. You can see the alignment with a taut string, it's pretty good, but the shot of it on the tiller viewed from the right side shows how the limb tip was kicking out to one side mostly due to the twist. The work on the tip and some carefull tillering has improved that considerably. In the shot of the bow on the tiller you can see the twist on the right limb if you click on it to see the pic full size, it makes the tip half of the limb appear too thick.
You can see the curve of the two limbs is more even now compared to the previous post.
With a bit of luck I might have it shooting tomorrow in time for the end of month 3D shoot at the club on Sunday. I'm not going to rush it though.