Please Let me know what are the giles i have to download for the offline updates of Nano Antivirus.
and is it possible to have the updates by dates in respective folders.

To update NANO AntiVirus in the offline mode you have to download the all content of ftp://updates.nanoav.ru by any ftp-client or download manager (anonymous ftp access is allowed). Then drag the downloaded files on a computer with installed NANO AntiVirus. Then in the update settings as an update source, select "Folder (network path), and specify the location of the folder with the downloaded files. Save your changes and run the update.
As for your second question, we don't store the updates by date.