Another roll your own technique would be to use a canvas and add the 'thumbnails' as embedded widgets. Here is an example (excerpt) that creates a 'static' sort, but you can imagine adding arbitrary images dynamically. This example also show how to associate callbacks when the 'thumbnails' are clicked.

my ($img_config,$img_control,$img_help,$img_vocabulary);
   
$img_config=$panel_canvas->Photo(-file=>LIB_PATH."/Perlbox/pixels/conf
+ig.gif");
$img_control=$panel_canvas->Photo(-file=>LIB_PATH."/Perlbox/pixels/con
+trol.gif");
$img_help=$panel_canvas->Photo(-file=>LIB_PATH."/Perlbox/pixels/help.g
+if");
$img_vocabulary=$panel_canvas->Photo(-file=>LIB_PATH."/Perlbox/pixels/
+vocabulary.gif");

$lbl_control=$panel_canvas->Label(-text=>"Control",-bg=>'#ffffff',-fg=
+>'#2c6997',-relief=>'flat');
$panel_canvas->createWindow(15,65, -window=>$lbl_control, anchor=>'nw'
+,-width=>54,-height=>15);

$lbl_vocabulary=$panel_canvas->Label(-text=>"Vocab",-bg=>'#ffffff', -f
+g=>'#2c6997', -relief=>'flat');
$panel_canvas->createWindow(15,145,-window=>$lbl_vocabulary, -anchor=>
+'nw',-width=>54,-height=>15);
   
$lbl_config=$panel_canvas->Label(-text=>"Config",-bg=>'#ffffff', -fg=>
+'#2c6997' ,-relief=>'flat');
$panel_canvas->createWindow(15,225, -window=>$lbl_config, -anchor=>'nw
+',-width=>54,-height=>15);
   
$lbl_help=$panel_canvas->Label(-text=>"Help",-bg=>'#ffffff', -fg=>'#2c
+6997' ,-relief=>'flat');
$panel_canvas->createWindow(15,305, -window=>$lbl_help, -anchor=>'nw',
+-width=>54,-height=>15);
[download]

For the full source, download Perlbox-Voice from Perlbox.org