Fixing problems on a site that only breaks on IE7

I did a new Drupal theme for my site based on the Zen theme. Since I am on Windows 7, I did testing with IE8, Firefox 3.5, and the most recent version of Chrome. The site looks great in all of those, but I just fo开发者_运维百科und out that it breaks on IE7. Unfortunately there is no way to put IE7 on Windows 7, so I'm at a loss for how I am going to find the exact cause and test a fix without flagging down a friend with IE7 on Vista or older.

My hope is that someone here might see what the issue is and point it out as something obvious. My HTML and CSS fu is not strong.

The site in question and some specific pages: http://byswarm.com/ http://byswarm.com/setting-concept/mejijpunk http://byswarm.com/page/plan

Any help would be greatly appreciated.

If you can use Microsoft Virtual PC. you can get IE6, IE7, IE8 VPC image free for development.

http://www.microsoft.com/downloads/details.aspx?FamilyID=21eabb90-958f-4b64-b5f1-73d0a413c8ef&displaylang=en

Use Sun VirtualBox (freeware) to create Virtual Comps with Windows XP (for IE7) and Windows 2000 or 2003 (for IE6), also recommend to install additionally IEDevTools (tools like Firebug for Firefox) for these IEs...
For fast previewing pages in IE you can use IETester (support 5,6,7,8 versions of IE)

Normally IE8 has a button right to the address bar where you can display it rendered by IE7. If not, you can always try this header, that forces IE8 to render as IE7: