Hello jhorowitz,
I think I have a workaround for your spider chart: see
https://github.com/yeslogic/prince-scripts/tree/master/compatibility/Highcharts/compat.jsThis is a script that tweaks Prince's DOM and JS environment slightly in order to make it more compatible with Highcharts. I've tested it against the demo you linked to and it seems to make it render OK.
Note that some parts of this script are hackish, and might cause a fallout for other scripts running on the same page. Feel tre to try to tweak the values and/or the script locally if it helps for your specific projects..
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