Sorry, but ColorEdge is not compatible with Mental Ray. Although is included with 3DS, really Mental Ray is very different from the standard scanline renderer, and uses its own material plugins (shaders).
The big problem to release it, is that MR considers all edges as visible... the 'edge visibility' values are stripped from scene when is exported to MR, but we need this information for ColorEdge. We have plans to release a new version of the plugin (possibly after completing Forest 3.2), but i don't know if we will found some fix for this issue.
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