First public release, there will probably be bugs (report them plz).
Setup
Extract the Mways_to_Rman folder into your Maya script directory. Drag the "run.py" into the script editor's Python tab, then select the snippet and middle-click drag it into a shelf of your choice. Save your shelf when done.
Usage
Import the model into Maya, select all the transform nodes for each of the block types you want to convert. Click the shelf button to begin the process.
For more info, check the readme.