Packing custom XCU with custom build

Hi,
I have created a custom XCU and schema. I want to distribute these files
with my own OOo build. I have modified already a lot of makefiles and .lst
files, but the build script doesn't pack my files. I haven't found any
documentation either.
Which files do I have to change, to add my files to the build process? Do I
have to localize a XCU? What's the meaning of all the constants in
build.lst? I haven't found any reference to the names anywhere else.

Thanks

eymux