Ok. I followed these instructions and now the plugin works, but only the favorites button can not be hidden. Why this happens? Below is the code I use:
$template_sub_menu = <<<EOT
<table cellpadding="0" cellspacing="0" border="0" width="100%">
<tr>
<td width="50%"></td>
<!-- BEGIN home -->
<td><img src="themes/mac_ox_x/images/menu_button_bg_left.gif" border="0" alt="" /><br /></td>
<td style="background-image:url(themes/mac_ox_x/images/menu_button_bg_middle.gif);" valign="top">
<a href="index.php"><img src="themes/mac_ox_x/images/home.gif" border="0" alt="" /><br /></a>
</td>
<td><img src="themes/mac_ox_x/images/menu_button_bg_right.gif" border="0" alt="" /><br /></td>
<!-- END home -->
<!-- BEGIN custom_link -->
<td><img src="themes/mac_ox_x/images/menu_button_bg_left.gif" border="0" alt="" /><br /></td>
<td style="background-image:url(themes/mac_ox_x/images/menu_button_bg_middle.gif);" valign="top">
<a href="{CUSTOM_LNK_TGT}" title="{CUSTOM_LNK_TITLE}">{CUSTOM_LNK_LNK}</a>
</td>
<td><img src="themes/mac_ox_x/images/menu_button_bg_right.gif" border="0" alt="" /><br /></td>
<!-- END custom_link -->
<td><img src="themes/mac_ox_x/images/menu_button_bg_left.gif" border="0" alt="" /><br /></td>
<td style="background-image:url(themes/mac_ox_x/images/menu_button_bg_middle.gif);" valign="top">
<a href="javascript:;" onmouseover="MM_showHideLayers('SYS_MENU','','show')">@</a>
</td>
<td><img src="themes/mac_ox_x/images/menu_button_bg_right.gif" border="0" alt="" /><br /></td>
<!-- BEGIN album_list -->
<td><img src="themes/mac_ox_x/images/menu_button_bg_left.gif" border="0" alt="" /><br /></td>
<td style="background-image:url(themes/mac_ox_x/images/menu_button_bg_middle.gif);" valign="top">
<a href="{ALB_LIST_TGT}" title="{ALB_LIST_TITLE}">{ALB_LIST_LNK}</a>
</td>
<td><img src="themes/mac_ox_x/images/menu_button_bg_right.gif" border="0" alt="" /><br /></td>
<!-- END album_list -->
<!-- BEGIN lastup -->
<td><img src="themes/mac_ox_x/images/menu_button_bg_left.gif" border="0" alt="" /><br /></td>
<td style="background-image:url(themes/mac_ox_x/images/menu_button_bg_middle.gif);" valign="top">
<a href="{LASTUP_TGT}" onmouseover="MM_showHideLayers('SYS_MENU','','hide')" title="{LASTUP_LNK}">{LASTUP_LNK}</a>
</td>
<td><img src="themes/mac_ox_x/images/menu_button_bg_right.gif" border="0" alt="" /><br /></td>
<!-- END lastup -->
<!-- BEGIN lastcom -->
<td><img src="themes/mac_ox_x/images/menu_button_bg_left.gif" border="0" alt="" /><br /></td>
<td style="background-image:url(themes/mac_ox_x/images/menu_button_bg_middle.gif);" valign="top">
<a href="{LASTCOM_TGT}" onmouseover="MM_showHideLayers('SYS_MENU','','hide')" title="{LASTCOM_LNK}">{LASTCOM_LNK}</a>
</td>
<td><img src="themes/mac_ox_x/images/menu_button_bg_right.gif" border="0" alt="" /><br /></td>
<!-- END lastcom -->
<!-- BEGIN topn -->
<td><img src="themes/mac_ox_x/images/menu_button_bg_left.gif" border="0" alt="" /><br /></td>
<td style="background-image:url(themes/mac_ox_x/images/menu_button_bg_middle.gif);" valign="top">
<a href="{TOPN_TGT}" onmouseover="MM_showHideLayers('SYS_MENU','','hide')" title="{TOPN_LNK}">{TOPN_LNK}</a>
</td>
<td><img src="themes/mac_ox_x/images/menu_button_bg_right.gif" border="0" alt="" /><br /></td>
<!-- END topn -->
<!-- BEGIN toprated -->
<td><img src="themes/mac_ox_x/images/menu_button_bg_left.gif" border="0" alt="" /><br /></td>
<td style="background-image:url(themes/mac_ox_x/images/menu_button_bg_middle.gif);" valign="top">
<a href="{TOPRATED_TGT}" onmouseover="MM_showHideLayers('SYS_MENU','','hide')" title="{TOPRATED_LNK}">{TOPRATED_LNK}</a>
</td>
<td><img src="themes/mac_ox_x/images/menu_button_bg_right.gif" border="0" alt="" /><br /></td>
<!-- END toprated -->
<!-- BEGIN favpics-->
<td><img src="themes/mac_ox_x/images/menu_button_bg_left.gif" border="0" alt="" /><br /></td>
<td style="background-image:url(themes/mac_ox_x/images/menu_button_bg_middle.gif);" valign="top">
<a href="{FAV_TGT}" onmouseover="MM_showHideLayers('SYS_MENU','','hide')" title="{FAV_LNK}">{FAV_LNK}</a>
</td>
<td><img src="themes/mac_ox_x/images/menu_button_bg_right.gif" border="0" alt="" /><br /></td>
<!-- END favpics-->
<!-- BEGIN search -->
<td><img src="themes/mac_ox_x/images/menu_button_bg_left.gif" border="0" alt="" /><br /></td>
<td style="background-image:url(themes/mac_ox_x/images/menu_button_bg_middle.gif);" valign="top">
<a href="{SEARCH_TGT}" onmouseover="MM_showHideLayers('SYS_MENU','','hide')" title="{SEARCH_LNK}">{SEARCH_LNK}</a>
</td>
<td><img src="themes/mac_ox_x/images/menu_button_bg_right.gif" border="0" alt="" /><br /></td>
<!-- END search -->
<td width="50%"></td>
</tr>
</table>