I'm having a similiar problem, possibly someone could help me out with. I have an mmUltraDataTimeEditor on my form. I bind it with the following code:
this.txtsd_dob.DataBindings.Add("Text",dsStudentInfo,"ST_STDNT.sd_dob");

In the bizobject for table ST_STDNT, I add a rule: this.AddRequiredField("sd_dob");
However, when I break this rule by leaving the field blank, I do not receive an error broken warning/icon.

I also have another mmUltraDateTimeEditor on my form. I set up a rule in the CheckRulesHook method. When I break the rule set up for this field, I receive the error warning, but alas no icon.

Is there any know error for the mmUltraDateTimeEditor not working properly with the error providor?

Thanks in advance for any help provided!!