I have overcome the problem with missing wx libraries by configuring it like this:
../configure --enable-debug-flag --enable-monolithic --disable-shared --enable-unicode --enable-postscript --enable-precomp-headers --with-expat=builtin --with-libjpeg=builtin --with-libpng=builtin --with-zlib=builtin
I.e. if the XCode project relies on those libraries being built by wxWidgets then we must ensure that wxWidgets builds them regardless of whatever else may be installed on the machine.
However, now I've hit another problem: Although --enable-postscript is specified and I can see that wxUSE_POSTSCRIPT is defined as "1" in setup.h I'm getting a compilation error in osrndrgn.cpp:
/Users/phil/Code/Arobs/XaraLX/wxOil/osrndrgn.cpp:1590: error: 'wxPostScriptDC' has not been declared
Did you have the same error? Got a solution?