[Dylanblitz]

The first part is easy, not sure how to do the second part, although I know what's wrong.

You want to stay away from using # as a value. I would add a line to the style like this

<a rel="nofollow" href="forumdisplay.php?f=$foruminfo[forumid]&letter=num">#</a></td>

Then change the plugin to be this

if($letter == 'num')
{
$hook = " AND LEFT(thread.title, 1) REGEXP ('[0-9]')";
} else {
$hook = " AND LEFT(thread.title, 1) = '$letter'";
}

The second part is happening because you are not adding the letter to the link. You need to add it to the pagenav, probably through the pagenav_complete hook, not sure exactly how you would do it though.

Another thing wrong I see. The page count is off when you select a letter. The page count is still counting all threads, even if they're not shown. So you might have 8 pages shown up top even if you only have 4 threads. I'm not sure if there's a hook to modify the total page count.

Sorry I couldn't help you more.