There is an article my partner published on our company website. We’ve spent some time working with custom connectors and experimenting with different types of integrations with Dynamics 365, CDS and Power Platform. If you are interested to learn more about PCF controls and how to combine all above together in a working solution it will be a good reading for you.
(The below has been described and tested for Canvas Power Apps. This has not yet been tested and adapted for Model-driven apps. As for the Power App Portal app, another integration pattern is appropriate, to be discussed later)