Hi Ivo
I found an interesting anomaly with the page pre-loader particle. On my test site, the only page it blocks is the standard gantry error page/template. When I remove the atom for that page, all is well, put it in and white page.
It appears to want to call jquery and that doesn't exist in joomla anymore, apparently. So why does it work on all pages except this one? Strange one. Hope you enjoy the bug hunt :-)
Regards
David