I've updated the root post with a new version that is not case-sensitive by default.
and doesn't support for unicode
Unicode seems to work OK here. For example, a folder named post❤test and this as the command:
GoParallel find="\prod\" replace="\post❤test\" TOGGLE SELECT PARENT
But note that Opus versions before 12.9.2 beta could not load or save buttons which contained characters outside the BMP range (UTF-16 surrogate pairs and 4-byte UTF-8 sequences). So you may have been running into that problem, rather than an issue with the script itself.
(In fact, it was trying to call the example button in the screenshots Prod 
Post which meant we found & fixed that problem.)