After some hit & trial I have managed to eke out somthing useful.
I edited /mnt/sda1/cde/onboot.lst to append multiple filename.tcz
i also copied desired tcz file alongwith md5sum & dep file to /mnt/sda1/cde/optional.
Now I get firefox,opera,pcmanfm,foxit installed by default.
Though booting takes few seconds more.
I could not find openjdk in tiny core repository?