How to modify the rom version and rom date?

[reglyj]

I've cooked my own rom
and I want to modify the rom date
How can I do that?

I found this file
xda3nbftool.exe
but it's said something like
calculate crcsum
updates crcsum
encrypt rom
...

if I modified the rom date, do I need to update the crcsum?
or what's does the encrypt option do?
if I encrypted the rom, must I input the password when I flash the rom???

thank you very much.