[Mathias]

What you're describing all sounds correct, so I'm not sure what's not working.

    <portal
      id="skill"
      style="menuNormal">
      <menu_things
        field="advSpecial"
        component="Skill"
        maxvisible="10"
        usepicks="hero">
        <candidate><![CDATA[
          !component.SkillGroup & !Hide.Skill & (!SkillHelp.NoSpecial | SkillHelp.UsingGroup)
          ]]></candidate>
        </menu_things>
      </portal>