Hi Remco,
to solve this issue we should check if some of the plugins you are using in your site is in conflict with spin360 plugins…
The easiest and suggested option would be to follow these steps:
https://kb.yoast.com/kb/how-to-check-for-plugin-conflicts/
1) deactivate all plugins
2) activate spin360 and check if the page I made is working
( https://phallix.nl/testing/ ) this page is visible only when you are logged as administrator (it is a private page with a minimal shortcode example)
If this still fails my plugins may have something in conflict with your theme.
In case the spinning page will display correctly, proceed as following:
3) enable one by one each plugins you need and see if the page is still correctly displayed (keep ‘Easy Facebook Likebox’ and ‘webwinkelkeur.nl’ sidebar as latest because we already know they have some issues also in a plain page)
4) when you found the plugins which is breaking the spin360 functionality, please post its name here an I will check locally what I can do to improve my plugins compatibility.
Thx for your collaboration