Sure - if you want to try Firefox you can download it here:
http://www.mozilla.org/en-US/firefox/new/
However, I am still not able to get a form to show up on my own, for instance on the Contact page.
After you paste in the form and click Preview, do you see the form in the preview window?
What exactly happens when you click the blue Update button? Does the form code disappear from the editor? The page on the public side?
I wonder if you'd mind taking a few screenshots (JPEG, PNG or PDF format, if possible) of what you see at some of the steps above where things aren't working as they should, to help in troubleshooting.
Here's a guide on how to make a screenshot, if you're not sure: http://en.support.wordpress.com/make-a-screenshot/
Once you've taken them, you can upload them to your Media Library and post links here so I can take a look.