I went to your site and downloaded the form backup file and installed it 1:1 on my test blog, changed the admin email & FROM address, but nothing else.
It works like a charm.
I also went back to your test page and submitted a form it all looked ok, did you get any email(s)?
I did not receive the auto confirmation yet that I got ealier when I tested the form on my blog, so this could in fact be an email issue.
To simplify testing, can you use simple email addresses a@b.c , no fancy names in quotes etc?
Worst case, what you may want to do, (*after* backing up your WP database AND making backups of all your forms!) is to erase all cforms data (under global settings), deactivate and reactivate the plugin and restore the forms 1 by 1.
Are you tracking the submissions, if so, is the data being tracked properly?