This affects IE10 users in both desktop and Metro modes. There are two ways to fix it – pick the one that works best for you.
Set document mode to IE9
Open the web page that hosts the gallery in a text editor. In most installations this is default.aspx in the root directory. Look for this line near the top:
<meta content="IE=edge,chrome=1" http-equiv="X-UA-Compatible" />
Change it to this:
<meta content="IE=9,chrome=1" http-equiv="X-UA-Compatible" />
This tells IE to run the page in IE9 document mode instead of the latest IE10 mode. Filters are still available in IE9 mode, so the dialogs work again.
This is an easy fix that has the added benefit of potentially fixing other IE10 issues that haven’t yet surfaced.
Apply the patch
I updated the 2.6.1 source code to change the transition effect of all dialog controls from Fade to None, effectively stopping ComponentArt from attempting to user filters on the page. Several files were modified, so I assembled them into a patch file that you can copy over the existing files of your website. The patch is located on the download page.
The advantage of this fix is that the gallery continues to run in IE10 document mode. I’m not sure what practical effect this has, but I always prefer to run under the latest when possible.