Installed mti_3.2.12.1 into Maya 2011 x64 (running Windows 7 x64) and the Plug-In/Indigo Shelf seems to be working....
Running Indigo Renderer v.3.2.12 x64 (stand-alone)
In Maya, when i click on "Talk to Indigo" i get this error:
// Error: No object matches name: mti_settings.mti_saveLocation
or "Options" button
// Error: No object matches name: mti_settings
I have attempted to wipe and re-install the plugin several times without success. Hopefully this is a easy and quick fix

~ Tonic