When using Stackla's fluid widget some other content loaded within your website may interfere with the light-box expanded-tile view of Stackla content.
We've noticed this issue with some Flash based ads (See image for an example). If you've encountered this, there's a nifty article here that will help solve the problem. Please keep in mind this may be browser related.
If your website developers have worked through the solution provided in the article above and you're still having troubles, please send an email to firstname.lastname@example.org or submit a request and our support team will get back to you.