Hi Glad,

    Basically, the file can be downloaded, (re)named to be bootstrap.dat and then used with graind, to fast track the initial sync.
    Once the sync has completed it can be used with specific addnode entries to connect with other peers to (re)establish the Grain swarm.

    Though, you may want to look back a couple of pages in the thread regarding the proposed and ongoing efforts from bee7.
    Currently, the main use of the bootstrap.dat is so you may get your wallet going again to be able to check a balance.

Best Regards,
-Chicago