Dave Haygarth (owner of ukcyclocross.com) decided to make a short clip of how absoluteBlack CX chainring works. Quite nice vid!http://www.youtube.com/watch?v=XDQEqgcqcQo&feature=youtu.be
As to chain. I have already sorted DanW. This was KMC chain issue and now it works fine. You have to use Shimano, Sram or any other chain, just not KMC. I can't go into many details, but chain retention DOES NOT depend on how tight the fit between chain/chainring is exactly. Even worn chainring will hold the chain well. It's hard to explain without telling secrets:).
To reiterate. These chainrings work very well in the mud, and i already have Mical Dyck (#1 in Canada) racing these chainrings in full muddy conditions with no problem.
They do not work well only with KMC chain +mud. This is because KMC chain have bigger dimensions of the rollers and the chain will clog up when you add mud (this further reduces the clearance). They know about this issue and they will work on that. So very soon you will see revised chains which will work with my chainrings as well:)
watch the video.
and this is how muddy you can ride in and still be fine. It's one of my customers photo:
I don't think you will get close to that on CX.