Thanks, that has done the trick, I just have to alter the path and try it again now.
edit:
Well I managed to edit the path and the autoconf.h as directed in the wiki page for the VX747. However now it brings up a problem with the rockbox logo very early in the build process . The message says : make: *** No rule to make target '/rockbox/build/apps/bitmaps/native/rockbox/buildlogo.320x98x16.o, needed by '/rockbox/build/bootloader.elf' . Stop.
Unfortunately I am not knowledgeable enough to correct this problem alone, does anyone know what to do here? Alternatively is anybody else able to compile a bootloader build for this target, could they contact me and we can arrange for them to email the necessary files from a recent build. Thanks to anyone who might help.