The problem
I've just encountered an issue with FPSS 3.5 and not being able to sort. Some further investigation found another component using JQuery was clashing. On discussion with that extension's developer (as he releases updates faster than JoomlaWorks) he spotted that FPSS is loading it's own older version of JQuery still, even though Joomla 3.2 loads it's own JQuery - so in loading it twice, it breaks the sort functionality in the backend of sorting the slides in FPSS by clashing between versions.
The workaround
Using NoNumber ReReplacer, I've been able to fix the issue by replacing the following three lines that call the FPSS copy of the JQuery scripts, leaving just the core Joomla JQuery loading.
<script src="/administrator/components/com_fpss/js/jquery.min.js" type="text/javascript"></script>,<script src="/administrator/components/com_fpss/js/jquery.ui.custom.min.js" type="text/javascript"></script>,<script src="/administrator/components/com_fpss/js/jquery.uniform.min.js" type="text/javascript"></script>
The long term fix
Joomlaworks, please update FPSS so that it doesn't load it's own JQuery in the Joomla 3.2 version by detecting either the version of Joomla, or working out loading it only if it's not available.