I have installed the widgets module on Silverstripe3.1
Created the flickerWidget and the widget is added to Default Sidebar widgetArea.
Flicker fields like PhotSet, UserID is set.
On the template Page made following changes to show the Widgets
page.ss
<% include SideBar %>
<div class="content-container unit size3of4 lastUnit">
<article>
<h1>$Title</h1>
<div class="content">$Content</div>
</article>
$Form
$PageComments
<% loop $WidgetArea("Sidebar") %>
$WidgetHolder
<% end_loop %>
</div>
it is not showing the Flicker widget.