Hah, maybe that was the issue! My image is not big enough
Based purely on visual debugging, you might want to add an artificial delay to the image loading. Maybe all the way back to resolving the image CDN/source http request after the accordion/collapsible containers have started rendering.
OS: Windows 7 with all updates
Browser: Chrome Version 57.0.2987.133 with 56 tabs open (don't ask)
H/W: Excess processor and memory
Time permitting, I could try to setup a dummy story and record a chrome timeline for you. I just need to ensure it contains no identifiable data, unless you have a hosted sandbox version of rally somewhere?