This is rather strange, as i convert all the materials down to cinema4d Materials and set the Renderer to the standard renderer.
def getDefaultRenderData(self , doc, imageWidth=1024, imageHeigth=1024):
renderData = doc.GetActiveRenderData()
renderData[c4d.RDATA_SIZEUNIT] = c4d.RDATA_SIZEUNIT_PIXELS
renderData[c4d.RDATA_PIXELPRESET] = c4d.RDATA_PIXELPRESET_SQUARE
renderData[c4d.RDATA_XRES] = imageWidth
renderData[c4d.RDATA_YRES] = imageHeigth
renderData[c4d.RDATA_PIXELRESOLUTION] = imageHeigth
renderData[c4d.RDATA_RENDERENGINE] = c4d.RDATA_RENDERENGINE_STANDARD
return renderData
The corona renderer is not involved except that there is a installation with a running out trial.