Hi Miller, browsing your s_loader.c code i realized there's a separate case called .pd_imac, which seems to be .pd_darwin for Mac/Intel. I don't think this is necessary (and i find it rather confusing), as separate build architectures are correctly recognized by the OSX loader routines. I just made a xsample universal build external which loaded just ok. To combine binaries you would use lipo, as in lipo -create i386/xsample.pd_darwin ppc/xsample.pd_darwin -o ub/ xsample.pd_darwin
greetings, Thomas