Hello Rilder,
I noticed, IE seems to have more trouble with topics than FF. That can be due to conflicting coding styles of HTML, perhaps even erratic coding (FF accepts it, IE doesn't/struggles).
Have you tried the Vanilla skin or one of the IBulletins? They seem faster with IE.
I'll try to restore the other styles to performing shape (there are some odd issues with it and non FF browsers). That may take some time.
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