Nmap http-joomla-brute script example?

This is a relatively obscure topic, but any help is nevertheless appreciated.

I am trying to run a brute force test on my website's Joomla login. I was trying to use nmap's http-joomla-brute, but for some reason it does not output neither the process nor does it actually do the brute force with the password list I gave it. Here is my script:

nmap -sV --script http-joomla-brute --script-args 'passdb=/Users/abc/Documents/passwords.txt,http-joomla-brute.threads=5,brute.firstonly=true' my.website.here.

I think it only runs the initial testing(which is really annoying BTW, does anyone have a way to avoid/skip it?) and the default password list, because it shows something like "1495 passwords tested" and my password list is 496 MB and definitely more than 1495 passwords. What am I doing wrong?

Thank you in advance.

EDIT: Fixed the script partially running, but now it does this:

Starting Nmap 6.40-2 ( http://nmap.org ) at 2014-04-02 19:39 EDT
Stats: 0:02:21 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 0.00% done
Stats: 0:03:41 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 0.00% done
Stats: 0:05:46 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 0.00% done
Stats: 0:05:50 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 0.00% done
Stats: 0:05:51 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 0.00% done
Stats: 0:05:51 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 0.00% done
Stats: 0:05:52 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 0.00% done
Stats: 0:05:52 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 0.00% done
Stats: 0:05:52 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 0.00% done
Stats: 0:07:18 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 0.00% done
Stats: 0:15:55 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 0.00% done
Stats: 0:16:03 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 0.00% done
Stats: 0:17:50 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 0.00% done
Stats: 0:22:06 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 0.00% done
Stats: 0:22:22 elapsed; 0 hosts completed (1 up), 1 undergoing Script Scan
NSE Timing: About 0.00% done

I don't think this is normal. Is there a way to fix this?

See the documentation for the unpwdb NSE library, which http-joomla-brute uses to manage usernames and passwords. It defaults to a 10-minute time limit, after which it stops returning credentials. If you really want to run it until it is finished, pass the unpwdb.timelimit=0 script argument to disable the timer.

Regarding the "initial checks" that you would like to skip, simply drop the -sV from your invocation, which will remove the service version detection phase of the scan, and add -p 80 to instruct Nmap to only scan port 80 (or whatever port your Joomla app is running on).