Sorry for late reply, i was away.
KMC chains will not work in mud for sure and this is written on the website. This is because inner rollers in the chain are bigger than industry standard. So if you add a mud in to the mix chain will go on top of the chainring as there would not be enough space.
Other chains work perfectly fine.
I have Mical Dyck using my chainrings (No1 in Canada in CX) and till now i have not heard from her that she encountered ant chain drop in muddy conditions.
Some chaindrops are a result of bad assembly of entire drivetrain or panic shifting in situations where most people do not change the gear. This is on rough terrain under load. Most people do not change the gear in such situation as you pedal on what you have or roll it over. To make it clear - chain will not fell off when you ride on same gear no matter what. It is only possible when you change the gear in worst possible moment for that.
There is also a picture above what this chainring can stand and still work. This photo is not photoshop'ed:) So for most people it works like it should. For those who don't i always try to find a solution. So just please send me the email if you are having trouble with the setup.
Here is also Dutch/German forum where people use my products in muddy conditions. All good opinions. http://forum.cx-sport.de/showthread.php?s=948af04348e1d624e89146b2a879248d&t=4424&page=2