Initially loaded slide has height of 0 - therefore invisible

I have set up VS with the below settings. I have inserted this into a drop-down menu to allow users to navigate groups of content from one menu item. The module works perfectly (thank you) but only after I specifically mouseover an item other than the slide that is the default. ie I get a list of navigable items on the left but blank space on the right until I mouseover the 2nd or 3rd (for example) item in the nav list. At that point the right-side populates correctly. If I return to the default slide then the hover it triggered and the right-side populates correctly.

I've discovered that once the page loads, the height of the first item is not being correctly set - ie it is 0. If I manually set this in a separate JS file or from the console then the first slide correctly displays and then the automatic sizing takes over correctly. I've used this code to do this:

$("class of views block").animate({height: 400})

Is there a setting that I've missed to get the first slide to correctly auto-size and therefore show?
Or, if I'm stuck with manually setting the height for the first slide, how can I calculate/read what the height should be because as I need auto-size this needs to be done on the fly and I can't work out where it is being read from or calculated as from looking at the code, the height is only calculated when I hover over a navigation item?

Any help would be really appreciated.

Many thanks,
Crom

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