1. I could not get the email function to work. It either wouldn't send it, or it would send it before the client entered their email address. I had tried changing from my Suffusion theme to a default theme, but it still didn't work. Finally, I changed the element ID of the field to something other than "email" (I used "emailadd") and it all worked.
2. I could not get the reset button to have the same appearance as the calculate and email buttons. So, I changed the function for the reset element to "button" from "reset" (front/tmpl-list.php) to get the button to look like the other buttons. There may have been css code I could have used, but I tried everything that seemed like it should work but I couldn't change the look of that button (though I am not familiar with any coding, so it was all trial and error).
3. I wanted the calculator to use the whole page. I found buried in a forum topic several months ago, to change the .jzzf_full (and/or _half, _third, _quarter) widths in front/themes/1.css. I did change those, and also the .jzzf_form_elements width. Worked like a charm. (Maybe next update will have this option?)
4. Something I couldn't get to work is formatting within the email, other than number formatting (like bold or underline). However, I am able to live without it (with a few extra elements).
Wish list (other than above): One thing that could be improved, is permitting the client to enter commas in the input field when they are entering numbers. (In my case, people will be entering numbers in the millions, and it is hard not to visualize the thousand separator commas while entering.) The second option I would like to see in the future, is not to do the calculation until the client pushes the "calculate" button.
Though it doesn't look like anything special, there are a lot of back calculations in this Jazzy Form calculator: http://keephome.store4info.com.
I can tell you that it took me about a month of reading past forums (in addition to trial and error) to make this plugin work for my needs. I encourage everyone to do the same, but wanted to help anyone who was having the same issues as me.
Thanks to all forum posters who helped others, and unknowingly helped me too. Many thanks to jazzigor for this great plugin! (Would love to see more documentation, but am glad you used your time to make it so robust.)