I have updated the Cycles for Rhino plug-in to be compiled against the current Rhino WIP release: 6.0.17073.13071, 17/03/14
Get it here: https://github.com/mcneel/CyclesForRhino/releases
There have been some changes to the core RhinoCycles plug-in that make it necessary to update to both current Rhino WIP public release and this new Cycles for Rhino plug-in release.
I’m seeing quite a few exceptions popping up on my list, those all relate to the core change, so please update as soon as possible. Thanks!