How do I get the most recent comments?

Using the example code at the bottom of my post (got it from the Lithosphere TKB) I can get the most recently kudoed messages, but I'm looking to list the most recent comments in our Idea Exchange.

I've tried all the combinations I can think of in the api call and I can't seem to get any data returned, apart from the example code.

I've changed

<#assign kudoedMessages = restadmin('/kudos/messages/leaderboard?max_age=one_week').messages />

 to all of these, with no luck:

<#assign kudoedMessages = restadmin('boards/id/ideaexchange/replies/').messages />

<#assign kudoedMessages = restadmin('boards/id/ideaexchange/replies/') />

<#assign kudoedMessages = restadmin('boards/id/ideaexchange').messages />

<#assign kudoedMessages = restadmin('boards/id/ideaexchange/').replies />

<!-- Create a macro that generates the list of recently kudoed messages in the community. We are using the same REST calls and      display logic used in the first application cache example -->

<#macro kudoedListDisplayM>
     <#assign kudoedMessages = restadmin('/kudos/messages/leaderboard?max_age=one_week').messages />
     <#assign kudoedList = [ ] />
     <#list kudoedMessages.message as m>
          <#assign authorUri = '/users/login/' + m.author.login />
          <#assign messageAuthor = restadmin(authorUri).user />
          <#assign authorAvatar = restadmin(authorUri + '/profiles/avatar').image />
          <#assign curr = { "message":m, "author":messageAuthor, "avatar":authorAvatar } />
          <#assign kudoedList = kudoedList + [ curr ] />
     </#list>

<p>Top kudoed messages:</p>
<p><ul>
     <#list kudoedList as k>
          <li>
          <p>${k.message.subject} </br>
                  <img src="${k.avatar.url}" />&nbsp;&nbsp;By: ${k.author.login}
          </p>
          </li>
       </#list>
     </ul>
</#macro>

 

<#assign kudoedListDisplay= appcache.get("kudoedListDisplay", "") />

<#if kudoedListDisplay != "">
<!-- kudoedListDisplay was NOT null, using cached value -->
<#else>

     <!-- kudoedListDisplay was null, populating list now using the macro created above-->
     <#assign kudoedListDisplay><@kudoedListDisplayM /></#assign>
     <#assign kudoedListDisplay = appcache.put("kudoedListDisplay", kudoedListDisplay) />
</#if>

<!-- Display the list -->

${kudoedListDisplay}

What am I doing wrong?