XPS/XNALara is an open-source tool available for Windows to pose 3D models and render high-quality images. Cochrane created an equivalent called GLLara that runs on Mac OS X, does the same as XNALara and tries to be as compatible as possible.
GLLara is fully localized in both English and German.
There is a development blog available where you can see the latest progress.
The latest and current version of GLLara is version 0.2.12.