Cannot disable visual editor – unable to set page width on text boxes

The text boxes for submitting a CV and Cover letter are completely messed up. I’ve manually changed code to set them to 750px, because the 100% saw them go from the normal left edge within the themes content margin all the way to the other edge of the page.

But this didn’t help. The problem appears to be the visual editor. The settings that toggle TinyMCE and the other formatting features don’t seem to work.

I even appied a page template that gives all the themes fixed width space (over 1000px) to the page, and still it stretches well beyond the boundaries of the theme on the right (theme is Mantra).

Not sure what else to do. The form is basically unworkable as is.

http://wordpress.org/extend/plugins/resume-submissions-job-postings/