Default boot menu selection in DSS V6 is set to boot in 64 bit. If you wish to change that here are few steps to take:

   If you wish to change iso file please use a proper tool to alter the files inside. If using USB stick changes can be made directly on the medium.

   Please navigate to folder 'b(buildname)/boot' and look for file called 'kernel.cfg'. Inside you will find a line 'MENU DEFAULT'. You can cut it and copy to the location under installer or 32bit section. Please pay attention to preserve the same pattern to avoid errors. If using iso file burn it on medium with proper software. Once the changes are saved DSS V6 should boot automatically in desired mode.