<mixin>
  <display-name>Attr: Options (radio)</display-name>
  <items>
    <item-set name="options">
      <label>Option</label>
      <items>
        <input name="optionValue" type="TextLine">
          <label>Value</label>
          <occurrences minimum="0" maximum="1"/>
        </input>
        <input name="optionText" type="TextLine">
          <label>Text</label>
          <occurrences minimum="0" maximum="1"/>
        </input>
        <input name="optionChecked" type="CheckBox">
          <label>Checked?</label>
          <occurrences minimum="0" maximum="1"/>
        </input>
      </items>
      <occurrences minimum="1" maximum="0"/>
    </item-set>
  </items>
</mixin>
<mixin>
  <display-name>Attr: Options (radio)</display-name>
  <items>
    <item-set name="options">
      <label>Option</label>
      <items>
        <input name="optionValue" type="TextLine">
          <label>Value</label>
          <occurrences minimum="1" maximum="1"/>
        </input>
        <input name="optionText" type="TextLine">
          <label>Text</label>
          <occurrences minimum="1" maximum="1"/>
        </input>
        <input name="optionChecked" type="CheckBox">
          <label>Checked?</label>
          <occurrences minimum="0" maximum="1"/>
        </input>
      </items>
      <occurrences minimum="2" maximum="0"/>
    </item-set>
  </items>
</mixin>
Set correct occurrence-values for radio buttons and the inputs for each option.
fix: Set correct occurrence-values for radio buttons and the inputs for each option.
