Have a look in /dopusdata\ConfigFiles\scriptcolumns.oxc - There might be multiple entries for the script and the filter may be pointing to an old one.
Before editing the scriptcolumns.oxc file, fully exit Opus (via File / Exit Directory Opus).
If you remove any entries in there related to the script, then re-launch Opus, and then delete and re-create the filter, does it start working?