Also in the admin the labels and fields are totally messy, please adjust it, this is one of the biggest sins in user interface design, not aligned input fields are a PITA for everybody. We are in 2012 and I feel thrown back into 1997 now looking at your plugin admin interface - please spend some time generating a form that can be used without pain.
http://s14.postimage.org/qfj74oeoh/WP_SI_CONTACTFORM_FAIL_02.png
I would not mention this in this explicity if your plugin was not specifically about FORMS - you should try to make your plugin a best practice demonstration of form design, not a worst case teaching example.
I totally can not understand how you released this into the wild without putting the needed one or two hours of form design work into it - beeing expert in everything related to forms of course involves designing your forms according to some well known user interface guidlines - there are many out there, please read at least ONE and accomodate with what is regarded nowadays as user friendly GUI building.
This could be a joke - hey, I make the coolest form plugin, but I totally miss to design the forms of my form plugin to adhere to minimal usability ideas. Unbelievable...