@Freddy It does work perfectly fine, if properly integrated.
You may check out bpmn-js-connectors-extension > example as a blueprint of a working integration. It does feature Camunda 8 but you may replace zeebe and cloud for camunda and platform to adapt it for Camunda 7.
For Camunda 7 you can refer to this test case that shows the integration, end-to-end.
All components shipped with Camunda Modeling tools are available standalone, too. Just sometimes not sufficiently documented.