> - Launch WinHTTrack, select 'Add URL'/'Capture URL' and 
> follow the instructions (change the browser proxy 
settings 
> accordingly)
>  
> Am I supposed to stay on this page with the ‘Set 
options…’ 
> button as I am clicking on the ‘submit’ button on my 
> webpage?  Or do I click next when I am done changing the 
> proxy settings?
No, let the dialog page as it, and click submit in your 
browser.

> - Restore your proxy settings
> Am I supposed to run anything within HTTrack before I 
> reset the proxy settings?  If not, how do I know that 
> httrack actually saved anything as far as the 
> authentication goes?
When hitting the "submit" button, you should see a page 
generated by httrack (which is your temporary proxy) 
showing that things were okay.

> Do I run the mirror putting the login page in as the web 
> address?
HTTrack should have already filled the address box with a 
new entry containing all necessary information (a file 
containing all relevant data)

The only thing to do at this point is clicking twice on 
the "NEXT" button