[K12OSN] further update questions

[Will Hatch]

I decided to just download the whole update selection that up2date said I needed (75 total).  On several of the updates I received this message: 

The package up2date-4.1.21-3 does not have a valid GPG signature.
It has been tampered with or corrupted.  Continue?

I just clicked yes to continue.  Also, after the packages were finished downloading I moved on to the installation screen.  Its been quite a while now and the progress bar hasn't even started.  The hourglass from my mouse is just hanging.  What might be happening here?  Thanks.