I played with Power Search 2.0/Elasticsearch 7.12.0 for a bit. I did the MSI with install as service and no joy. When I try to customize the plugin, clear search index takes about 20 seconds and returns:
calibre, version 5.14.0
ERROR: Power Search: Timed out waiting for ElasticSearch to start.
I added a dummy batch file containing "exit 0" to ensure that the attempt to start Elasticsearch returned success and no difference.
While waiting for the error message, I opened another tab in Firefox and it seemed to be happy as in the attached image.
I tried the zip file install, ran elasticsearch-service.bat install and then start and the service was installed and happily running. I then ran calibre, went into PowerSearch's configuration and exactly the same results.
If I try to run PowerSearch, I get a momentary popup and calibre closes.