only element I see that has an asterisk is the file element:
<label for="fieldset_group_Bild" class="sublabel" > Bild:<span class="requiredIndicator"> *</span></label>
you can change that to:
<label for="fieldset_group_Bild" class="sublabel" > Bild:</label>
it appears the file field will always have the asterisk in place regardless of validation, I have logged this as a bug to be fixed in a future release.