I did the manual installation with download from GitHub but get the following error message after activating the extension:
Fatal error: Class 'SESP\Annotator\ExtraPropertyAnnotator' not found in \bluespice\extensions\BlueSpiceSMWConnector\includes\BSExtraPropertyAnnotator.php on line 10
MediaWiki 1.27.3 | BlueSpice 2.27.2 | Semantic Extra Special Properties 2.0.0-alpha | BlueSpiceSMWConnector 2.27.3