On the self-contained project submission page (e.g. mydomain.com/cchost/submit/fullmix), the field immediately below "Submit a Self-Contained Project" displays "str_submit_original_help_line", whereas other submission pages display explanatory prose in the same field. For example, the "Submit a Derived Work" page (e.g. mydomain.com/cchost/submit/remix) displays "Use this form to submit a derived work." in the same field.
The problem seems to originate in ccHost/ccskins/shared/strings/all_media.php (in a default installation, i.e. in which "cchost" is the install directory), in which lines 759-760 use the same variable name twice:
$GLOBALS['str_submit_original_help'] = _('A self-contained project does not derive any material from outside sources. It is a totally original work.');
$GLOBALS['str_submit_original_help'] = _('Use this form to upload a self-contained project.');
The solution is to change second variable name from "str_submit_original_help" to "str_submit_original_help_line", so that lines 759-760 look like this:
$GLOBALS['str_submit_original_help'] = _('A self-contained project does not derive any material from outside sources. It is a totally original work.');
$GLOBALS['str_submit_original_help_line'] = _('Use this form to upload a self-contained project.');
Fixed Help Line Display