Damon, it looks like those settings are correct. You can play around with the type and shaping of the dither noise. I think I preferred "ultra" noise shaping with the Type 1 dither. In the manual somewhere there's a description of what each type and shaping option mean. I don't know if I have a pdf of that or not. I'll look around for that later.
If I'm doing a jazz show or something with a lot of dynamic range in 24-bit, I'll use the "high res CD master" preset in the L2 plugin to go to 16-bit. I assume the L1 has something similar.
There's a way to batch this job as part of a plugin chain, too. I do that when I've already split up the 24-bit file and want to make a CD copy. I batch resample and dither, then use SHNtool or something to fix sector boundaries.
Edit: Any idea what domain analog/digital means in that plugin?