1) Download latest libbzip2 from https://sourceforge.net/projects/bzip2/
   (used here: 1.0.6)
   Or download the iscompress project https://github.com/jrsoftware/iscompress
   and use its files - it also contains innosetup.c with a few misc functions
2) Compile Win32 version:
   bcc32 -c -DBZ_NO_STDIO -u- *.c
   and move the .obj files to win32
3) Compile Win64 version:
   bcc64 -c -DBZ_NO_STDIO *.c
   and move the .o files to win64
