Whoa there pardner.

I never said it was a problem with your file. I just thought you meant there was a problem in my $tbopen when you said, "...table tag somewhere that's killing off the html in the $tbopen variable." I guess I misread that.
And I don't know if I uploaded your copy of ubbthreads.tmpl from the old post. I have to fire up the ol' Beyond Compare later.
And I didn't know you wanted me to post my script. I'm new here, and if that's protocol, I wasn't aware and I'm sorry. I just thought the Infopop police didn't want entire scripts posted to the public.

But I'll attach it to this post.
Not trying to bad-mouth your hack. I do appreciate all the work you have put into it. Kudos! And let's all just get along.
P.S. I attached the file as a .txt and it turned out partially ran, so I'm just going to quote it below.
[]
<? //UBBTREMARK
echo <<<UBBTPRINT
$only_favs
$BirthdayGreeting
$tbopen
UBBTPRINT;
for($c=0;$c<$catsize;$c++) { //UBBTREMARK
echo <<<UBBTPRINT
<!-- CATEGORY LOOP START -->
<tr>
<td colspan="5" class="cleartable"><img src="{$config['images']}/blank.gif" width="1" height="1" alt="*" /></td>
</tr>
<tr>
<td align="center" valign="top" class="tdheader">
<table border="0" cellpadding="0" cellspacing="0"><tr><td class="{$catrow[$c]['NewMarker']}">
{$catrow[$c]['ToggleLink']}
</td></tr></table>
</td>
<td class="tdheader">
<img $imagestyle src="{$config['images']}/about.gif" alt="{$catrow[$c]['CatDesc']}{$catrow[$c]['NotShown']}" title="{$catrow[$c]['CatDesc']}{$catrow[$c]['NotShown']}" />
{$catrow[$c]['CatTitle']}
</td>
<td class="tdheader" align="center" width="9%">
{$ubbt_lang['THREAD_TEXT']}
</td>
<td class="tdheader" align="center" width="9%">
{$ubbt_lang['POSTS_TEXT']}
</td>
<td class="tdheader" align="center" width="40%">
{$ubbt_lang['LAST_POST']}
</td>
</tr>
<!-- BEGIN FORUM CODE LOOP _ DO NOT ALTER COMMENTS -->
UBBTPRINT;
for($f=0;$f<$forumsize[$c];$f++) { //UBBTREMARK
echo <<<UBBTPRINT
<tr>
<td valign="top" class="darktable">
<img src="{$config['images']}/{$forum[$c][$f]['boardfolder']}" alt="" />
</td>
<td class="darktable">
<font class="forumtitle">
<a href="{$config['phpurl']}/postlist.php?Cat=$Cat&Board={$forum[$c][$f]['Keyword']}">
{$forum[$c][$f]['Title']}
</a>
</font>
<br />
<table cellpadding="0" cellspacing="0">
<tr>
<td>
Â
</td>
<td class="forumdescript">
{$forum[$c][$f]['Description']}
</td>
</tr>
</table>
{$forum[$c][$f]['modlist']}
</td>
<td align="center" class="threadtotal" nowrap="nowrap">
{$forum[$c][$f]['Threads']}
{$forum[$c][$f]['showthreads']}
</td>
<td align="center" class="posttotal" nowrap="nowrap">
{$forum[$c][$f]['Total']}
{$forum[$c][$f]['showposts']}
{$forum[$c][$f]['showna']}
</td>
<td class="posttime" nowrap="nowrap">
{$forum[$c][$f]['lastpost']}
<br />
    Â
{$forum[$c][$f]['lastposter']}
- {$forum[$c][$f]['time']}
</td>
</tr>
UBBTPRINT;
} //UBBTREMARK
} //UBBTREMARK
echo <<<UBBTPRINT
<!-- END CATEGORY LOOP -->
<!-- END OF FORUM LOOP -->
</table>
</td>
</tr>
</table>
<br />
<!-- WHOS ONLINE BOX MODIFICATION START -->
$tbopen
<tr>
<td class="tdheader">
Who's Online
</td>
</tr>
<tr>
<td class="lighttable">
{$whosOnline}
</td>
</tr>
$tbclose
<br />
<!-- WHOS ONLINE BOX MODIFICATION END -->
$tbopen
<tr>
<td colspan="3" class="tdheader">
<b>{$ubbt_lang['B_INFO']}</b>
</td>
</tr>
<tr>
<td width="45%" valign="top" class="lighttable">
<span class="small">
$welcomemessage
<br />
$toggleshowstart
$currentshow
$toggleshowstop
<br />
$registered {$ubbt_lang['REGED_USERS']}
<br />
{$ubbt_lang['NEW_MEM']}
<a href="{$config['phpurl']}/showprofile.php?User=$encnewusername&What=ubbthreads&Cat=$Cat">
$newusername
</a>
<br />
{$ubbt_lang['C_ONLINE']} $r {$ubbt_lang['C_ONLINE2']} $a {$ubbt_lang['C_ONLINE3']}
<br />
$edittimelinkstart{$ubbt_lang['OFFSET_TIME']}$edittimelinkstop
$time
</span>
</td>
<td width="30%" valign="top" class="lighttable">
<span class="small">
<b>{$ubbt_lang['VIEW_PAST']}</b>
<br />
<a href="{$config['phpurl']}/dosearch.php?Cat=$Cat&Forum=All_Forums&Words=&Match=Entire+Phrase&Old=1day&Limit=25">
{$ubbt_lang['PAST24']}
</a>
<br />
<a href="{$config['phpurl']}/dosearch.php?Cat=$Cat&Forum=All_Forums&Words=&Match=Entire+Phrase&Old=2days&Limit=25">
{$ubbt_lang['PAST48']}
</a>
<br />
<a href="{$config['phpurl']}/dosearch.php?Cat=$Cat&Forum=All_Forums&Words=&Match=Entire+Phrase&Old=1week&Limit=25">
{$ubbt_lang['PAST7']}
</a>
</span>
</td>
<td valign="top" class="lighttable">
<b>{$ubbt_lang['LEGEND']}</b>
<table border="0" cellpadding="0" cellspacing="2">
<tr>
<td>
<img src="{$config['images']}/newposts.gif" alt="*" />
</td>
<td class="small">
 {$ubbt_lang['L_NEW']}
</td>
</tr>
<tr>
<td>
<img src="{$config['images']}/nonewposts.gif" alt="*" />
</td>
<td class="small">
 {$ubbt_lang['L_NONEW']}
</td>
</tr>
<tr>
<td align="center">
<img class="newpostsincat" src="{$config['images']}/catexpand.gif" alt="{$ubbt_lang['CATLEGEND']}" />
</td>
<td class="small">
 {$ubbt_lang['L_NEW']}
</td>
</tr>
<tr>
<td align="center">
<img src="{$config['images']}/catexpand.gif" alt="{$ubbt_lang['CATLEGEND']}" />
</td>
<td class="small">
 {$ubbt_lang['L_NONEW']}
</td>
</tr>
</table>
<!--Start of Birthday Mod - by JoshPet-->
<tr class="lighttable">
<td class="small" valign="top" colspan="3">
<b>$TodayIntro</b> $todaybday
<b>$MonthIntro</b> $thismonthbday
$BirthdayWarning
</td>
</tr>
<!--Birthday Mod End-->
</td>
</tr>
$tbclose
<br />
UBBTPRINT;
/* UBBTREMARK */ ?>
[/]