Same problem with the IE8 browser (I use XP Professional with SP3 and all framework, java or whatever is need, with the last version at all)
The forum works fine just with Firefox or Chrome browsers.
Please see the browser scroll position on the any right side of the attached pictures
Pictures orders from the left to the right: 1 -header of forum, 2- a little down scroll, 3 - next down scroll, 4 - scroll down again...
Maybe you must put in your forum header page (after the "<head>") something like this ?
<meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7; IE=EmulateIE9" />
Smile today, tomorrow could be worse
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