Very impressive! That's looking very close to done - I played with the CCD demo for a while, and I was able to make a board tunnel through the floor once, but I couldn't figure out how to repeat it (I think one board was vertical, pinned between two flat ones while the bomb hit, or something like that, didn't have it in step mode).
When you say it doesn't conserve time, do you mean it doesn't finish the time step if the CA step predicts a collision before it's up? Does this mean that the time between collisions is not bounded from below? I know this is asking a lot since you're so busy getting the engine working, so don't feel obligated at all, but once you have all this worked out, I would love to see a full explanation of the algorithm (I noticed that your post at http://www.bulletphysics.com/Bullet/phpBB3/viewtopic.php?f=4&t=1710&sid=2e2a43a492d5881a1ab01ad7c4bc4736
was met with silence, which disappointed me as I've found most CA explanations to be lacking details such as that one). If you can't get around to it, no big deal since the code is there, but I think it would fill a gap if it was clearly explained.
One little thing: I don't know if this is new to this version, but the pyramid demo looks like it's barely making it, it seems like it has a lot more give than it used to. Vertical stack also seems to wobble a little more than in the past. I don't think it's like that in 1.4.3 (Java port @ ~1.4.3 seems okay, though I don't have the C++ to check against, already updated to SVN), so it must have to do with the CCD stuff - assuming the pyramid blocks do not have that flag set, maybe the friction response against the floor in CCD mode is a bit off, leading to more slip than usual?
One last question: is this stuff going to be live in the next couple of releases? Should I start porting what you have, or is it going to change too much before it settles to be worth starting on now?
Looking good, in any case, I believe I've already mentioned how excited I am to use this feature in games...once this is stable I'll finally be able to nail the coffin on my hand-rolled engine and start worrying more about programming the games than the physics!