For Editors

You can just add {downloadLink} to your answer page and you are fine.

If you want the download link to be shown on the thx site after the user submitted his data you need to edit the Web.html template (Resources/Private/PowermailAll/Web.html) of powermail.

Snippet
<f:if condition="{0:answer.field.type} == {0:'downloadLink'}">
   <f:then>
      <f:format.html>{answer.value}</f:format.html>
   </f:then>
   <f:else>
      <f:format.nl2br>{answer.value}</f:format.nl2br>
   </f:else>
</f:if>
Example:
{namespace vh=In2code\Powermail\ViewHelpers}

<f:comment>
   Mail: {mail}
   Answer: {answer}
</f:comment>


<dt class="powermail_all_label powermail_all_type_{answer.field.type} powermail_all_marker_{answer.field.marker}">
   <vh:string.RawAndRemoveXss>{answer.field.title}</vh:string.RawAndRemoveXss>
</dt>
<dd class="powermail_all_value powermail_all_type_{answer.field.type} powermail_all_marker_{answer.field.marker}">
   <f:if condition="{vh:Condition.IsArray(val: '{answer.value}')}">
      <f:else>
         <f:if condition="{0:answer.field.type} == {0:'downloadLink'}">
            <f:then>
               <f:format.html>{answer.value}</f:format.html>
            </f:then>
            <f:else>
               <f:format.nl2br>{answer.value}</f:format.nl2br>
            </f:else>
         </f:if>
      </f:else>
      <f:then>
         <f:for each="{answer.value}" as="subValue" iteration="index">
            <f:if condition="{subValue}">
               {subValue}<f:if condition="{index.isLast}"><f:else>, </f:else></f:if>
            </f:if>
         </f:for>
      </f:then>
   </f:if>
</dd>

The extension adds to new fields to powermail form: downloadLink and file. If you don't want to have them on the thx site or in the email you need so filter them in the Web.html and Mail.html template of powermail.

Can look like this:
<f:if condition="{0:answer.field.type} != {0:'downloadLink'}">
      <f:format.nl2br>{answer.value}</f:format.nl2br>
</f:if>

The extension uses FPDM from fpdftk (http://www.fpdf.org/en/script/script93.php) which does not support check boxes in pdfs.

If you want to fill checkboses in the pdf you need to have pdftk (http://www.pdflabs.com/tools/pdftk-the-pdf-toolkit/) installed on your server. The the extension uses pdftk to create the pdf and checkboxes can be filed. (may not work yet)