In the latest official release of FusionCharts 3.4, the box and whiskers chart has an issue with data sets whose Q1 is equal to zero. I tried to create a JSFiddle to demonstrate the issue, only to find that the version of FusionCharts that's accessible externally has partially fixed this bug. Nevertheless, I've attached a screenshot to show what it looks like with the official release.
This JSFiddle is a test case which reproduces an the vertical line that can still be seen even in the latest unreleased version.
Live example:
http://jsfiddle.net/z8cthcf4/