Perch Form error...blocks related?

I have a form template which submits to the Forms app, which I've done many times. This is the first time I've used a blocks form template, though. There are also several forms on the one page which is unusual for me. Anyway, when a form is submitted, I get this error:

Fatal error: Call to a member function label() on a non-object in D:\{path removed}\addons\apps\perch_forms\runtime.php on line 25

Here's the form template:

<div class="formWrap">

    <h3 class="headS"><perch:content id="title" type="text" label="Title" required="true" title="true" /></h3>
    <perch:content type="image" id="thumb" label="Thumbnail Image" width="500" height="500" quality="80" no-index="true" required="true" suppress="true" />
    <hr>

    <perch:form id="<perch:content id="slug" type="slug" for="title" />" class="inqForm verlag" action="javascript:void(0);" method="post" app="perch_forms">

        <perch:blocks divider-before="Form Fields" >

            <perch:block type="text-input" label="Text Line">
                <div class="infieldWrap">
                    <perch:label for="<perch:content id="slug" type="slug" for="label" />"><perch:content id="label" type="text" label="Label" required="true" /><perch:content id="required" type="checkbox" label="Required" value="true" suppress="true" /></perch:label>
                    <perch:input type="text" <perch:if exists="required">required="true" </perch:if>id="<perch:content id="slug" type="slug" for="label" />" label="<perch:content id="label" type="text" label="Label" required="true" />" />
                </div>
            </perch:block>

            <perch:block type="email" label="Email">
                <div class="infieldWrap">
                    <perch:label for="email"><perch:content id="label" type="text" label="Label" required="true" /><perch:content id="required" type="checkbox" label="Required" value="true" suppress="true" /></perch:label>
                    <perch:input type="email" <perch:if exists="required">required="true" </perch:if>id="email" label="<perch:content id="label" type="text" label="Label" required="true" />" />
                </div>
            </perch:block>

            <perch:block type="yes-no" label="Yes/No">
                <div class="radioOuter">
                    <perch:label for="<perch:content id="slug" type="slug" for="label" />"><perch:content id="label" type="text" label="Label" required="true" /><perch:content id="required" type="checkbox" label="Required" value="true" suppress="true" /></perch:label>
                    <perch:input type="radio" options="Yes,No" <perch:if exists="required">required="true" </perch:if>id="<perch:content id="slug" type="slug" for="label" />" label="<perch:content id="label" type="text" label="Label" required="true" />" wrap="div.radioWrap" />
                </div>
            </perch:block>

            <perch:block type="message" label="Message">
              <div>
                <perch:label for="<perch:content id="slug" type="slug" for="label" />"><perch:content id="label" type="text" label="Label" required="true" /><perch:content id="required" type="checkbox" label="Required" value="true" suppress="true" /></perch:label>
                <perch:input type="textarea" <perch:if exists="required">required="true" </perch:if>id="<perch:content id="slug" type="slug" for="label" />" label="<perch:content id="label" type="text" label="Label" required="true" />" rows="<perch:content id="rows" type="text" label="Rows" size="xs" help="Height of message box in rows, e.g. '5'" required="true" />" encode="false" />
              </div>
            </perch:block>

        </perch:blocks>

        <div class="submitWrap">
            <perch:input type="submit" class="rectLink verlag" id="submit" value="Submit" />
        </div>

        <div class="clearfix"></div>

        <perch:success>
            <script>
                    return 'SUCCESS';
            </script>
        </perch:success>
        <perch:error for="all" type="general">
            <script>
                    return 'Perch Error';
            </script>
        </perch:error>
    </perch:form>

</div>

Page where template/forms are called:

<?php include('{removed}/runtime.php');?> 
<div class="inqPopWrap">
    <div class="royalSlider rsDefault">
        <div>
        <h3 class="headS">Inquire</h3>
        <hr>
        <?php
            perch_content_custom('Forms', array(
                'template'=>'/inquire/landing.html'
            ));
            perch_content('Contact Info');
        ?>
        </div>
    </div>
    <div class="inqHiddenForms">
        <?php perch_content('Forms'); ?>
    </div>
</div>

And here is diagnostics:

Perch: 2.8.11, PHP: 5.5.11, MySQL: mysqlnd 5.0.11-dev - 20120503 - $Id: bf9ad53b11c9a57efdb1057292d73b928b8c5c77 $, with PDO
Server OS: WINNT, apache2handler
Installed apps: content (2.8.11), assets (2.8.11), categories (2.8.11), perch_blog (4.6), perch_forms (1.8.3)
App runtimes: <?php $apps_list = array( 'content', 'categories', 'perch_blog', 'perch_forms', );
PERCH_LOGINPATH: {removed}
PERCH_PATH: {removed}
PERCH_CORE: {removed}
PERCH_RESFILEPATH: {removed}\resources
Image manipulation: GD
PHP limits: Max upload 1000M, Max POST 1000M, Memory: 500M, Total max file upload: 500M
Resource folder writeable: Yes
HTTP_HOST: {removed}
DOCUMENT_ROOT: {removed}
REQUEST_URI: {removed}/core/settings/diagnostics/
SCRIPT_NAME: {removed}/core/settings/diagnostics/index.php

Thanks for the help!

EDIT: I should also mention that the error/success messages are in <script> tags because this form is supposed to be AJAX submitted...but I still get the same error message when I submit directly from the page without AJAX.