toggleOverview mouse click issue about io-2012-slides HOT 7 OPEN

Which slide in particular does this happen for?

This happen in all the slides under toggleOverview mode (press O). But not all 
the time the click event is not available, you might refresh few times, then 
you will see this issue.

Demo site: http://io-2012-slides.googlecode.com/git/template.html#1 

suspect the issue related to slide.addEventListener('click', function(e)

Can you give me step by step how to repo this. I'm able to press "o", click 
either slide #1 or #1, and have it enlarge.

Step1: http://io-2012-slides.googlecode.com/git/template.html#1
Step2: Press O
Step3: Check if you can click any slide by using mouse click, if yes, please 
continue the step
Step4: Refresh
Step5: Go back to Step 2

Can't reproduce with those steps

Chrome version: Version 30.0.1599.101

My end refresh 2 times can produce this issue.

figured out. is the .loaded css problem. Added position:relative; z-index:0; 
can solve this issue. I think bcos of the timing to load .loaded class into 
body, that's why sometimes slide is under body overlay.