The delay might be caused by the file size of your background image. Try reducing the file size and see if that helps.

No, the background image is actually loaded later in the sequence. You can check the timeline of page loading using Firefox with Firebug extension. In fact, the same thing happens on your demo site

http://c5mix.com/demos/theme/clearview...

where menu-tab.png is loaded with a lag. (In your case, you are loading non-minified jquery.ui.js from your server, so that part is taking long, too, but on my site, I'm loading minified version from google apis server, so the lag stands out even more...

I tried to see if there's a way to save / print the timeline profile but I can't seem to... Would you try Firebug and profile the loading timeline of this theme?

Thanks!

Honestly, I'm not sure what the delay is from. On my demo on my computer, the menu-tab image loads after 73 ms and the white-bg after 132. I really dont even see a lag though when viewing the demo - those to files seem to load right away. Not sure what else to tell you.

That's very strange. I still see the lag, regardless of whether I measure it on your demo site or my own sitehttp://beaupix.com. Does that mean the lag might be due to network factor or OS/browser version/configuration? Well, at this point I just hope other users don't want for the page to load unnecessarily...

Thanks for checking.

Ryuji