Hi,
I wanted to do the same thing. I didn't want to hack into the cform system files which would mean I'd lose my changes with every update. Here's how I did it:
In the settings for the form in the WP admin area, where the fields, labels, etc. are set, for the textarea naming that element I added (I put this in < code > tags I hope it shows up properly on the forum page )
Email <span class="required"> – Required</span>
Then of course I put some styling for the span.required element.
To get rid of the default Required, I added "display:none!important;" to BOTH
classes .emailreqtxt and .reqtxt. These are applied to spans for the form elements. One is for the email, duh, and the other for any other element. The form requires the span for "required" (the one you want to get rid of) to function but this just makes it invisible. I put these classes and styles at the bottom of the cform stylesheet (a custom sheet so not overwritten). I have not solved one thing about this, tho… the textbox in the visible form as it shows up on the page is lacking the default "required" span below the textbox (in this case Email), and therefore it is a bit closer vertically to the next textarea & label below it. I think this will be do-able by turning on the IDs for the elements and setting some margin for each specific LI by ID.
Edit: last sentence… yes but not margin, padding-bottom.