Exporting 2D part outline data from Altium?
Have you looked at exporting your PCB as "ASCII"?  

http://www.eurointech.ru/products/Altium/Protel99SE_PCB_ASCII_File_Format.pdf

In my Altium, Mechanical 13 is the part outline layer. 



You could find this layer in the PCB file and parse though it, I think.