IsoDraw 7.2 32-bit color image export problem

I recently discovered an issue with exporting 32 Bit color images of lineart in IsoDraw 7.2 where lines appear jagged and not anti-aliased (Please view the full size images to see the issue):

However, if I export this same image as a 8 Bit grayscale image, the lines appear correctly anti-aliased:

Is this a bug in IsoDraw's export engine? This occurs with both PNG and JPEG files. Logically, the full 32 bit range of colors should have no issue properly containing the image information, but it appears IsoDraw is not anti-aliasing the lines on those exports.