(1) Where errors of law or procedure do not cause prejudice to a party or deny a party a fair hearing or fundamental justice, they may be disregarded. Parties who assign error for the violation of any rule must demonstrate that a failure to comply with these rules is in fact prejudicial or constitutes prejudice as a matter of law.
(2) Where strict adherence to these rules would cause undue hardship or create a substantial injustice to a party, the commission or hearing examiner may modify, waive, or excuse their application. The commission or hearing examiner may not modify, waive, or excuse mandatory acts which are required by statute or due process of law.
(3) Parties who choose not to be represented by counsel and who represent themselves must substantially comply with the provisions of these rules, subject to the provisions of (2) . A hearing examiner or the commission may modify the strict application of these rules to an unrepresented party to the extent they are not mandatory in order to assure a fair hearing.