You need to produce a 32 bit build of apitrace. You'll need multiarch/multilib
support in your distribution and 32-bit variants of certain packages (e.g. on
Debian/Ubuntu, install the g++-multilib package, and libwhatever-dev:i386 if
you get error messages for libwhatever). When running cmake, add the following
parameters:

-DCMAKE_C_FLAGS=-m32 -DCMAKE_CXX_FLAGS=-m32 -DCMAKE_EXE_LINKER_FLAGS=-m32
-DENABLE_GUI=FALSE

Traces recorded using the 32 bit apitrace can be played back on apitrace of any
bitness.