Next Limit has updated their plugins for SketchUp and Cinema 4D. These plugins allow you to work between the programs and Maxwell Render, using the latter as its target renderer.
Maxwell Render for SketchUp is now at version 2.5.15. It brings forth Maxwell Fire-based material preview and several changes and fixes. New auto-focus functionality has been added to the camera, new network rendering menu options, new output options and more. There are also several OS X fixes for those using SketchUp and Maxwell on Macs.
Maxwell Render for Cinema 4D is now at version 2. 5.1.6 is a minor bug fix only. The primary change here is the added support for QuickTime textures in Cinema materials. There were also several key fixes in this update, including a crash that occurred when creating a new material (on OS X/R11.5/R12/32-bit only) and a fix of redundant cameras during the exporting of animations.
Those are the latest updates for Maxwell Render. Also, back in late April Houdini was also officially supported with a plugin, compatible with Maxwell Fire as well. To learn more visit them online here.