Display issue

I am using a custom theme and when I place WFU into a page, the form looks very bad. If I switch to the Twenty-twelve theme, everything looks great. I have contacted the theme creator and he has been of no use, other than saying it may be a CSS conflict. I was wondering if anyone else had an issue with their theme or some ideas on what I could do to fix the issue.

https://www.ads-software.com/plugins/wp-file-upload/