All rows blank in grid

I've been having the same problem for a long time with the grid control, and it's very strange. When I load a page with a grid - any grid, alone or with others - in IE10 (or IE7 to IE9, for that matter), all of the rows are blank. The right number of rows are displayed, and they are nicely styled with alternating shading, I can see where the row headers should be (also blank). There are no vertical column lines, either.

I've got a screenshot here:
https://dl.dropboxusercontent.com/u/1125535/Blank%20AW%20grid.png

I've tried forcing the page to reload everything, I've done a full reset of IE settings back to factory defaults and I've found that the grid only displays at all with Compatibility View mode turned on. It used to work properly via a virtual machine, but that's giving me a different, unrelated error now (a SQL login problem). None of my colleagues at work, with the same setup, on the same website code - or even browsing it on their machines served from mine! - seem to have this problem.

Does anyone have any idea what could be going on?

Okay, on further inspection of the rendered page, some of the grid elements - CSS class "aw-item-box" - have widths of "999999px" (or something equally large) as set in the aw.css stylesheet. I'm guessing that width should be reined in by some bounding box, but that's not happening. It's just running wild, to its full tens-of-thousands of pixels width. Am I getting warmer?