I have come across the 'content management' powerapp that I would like to use. However, whilst I can preview it, I cannot edit it. Can anyone tell me what I am doing wrong?
Do you mean the "Property management" Sample App?
Currently it is not available to re-use sample apps listed under PowerApps home page. Please take a try to New an App from App template:
Create and run an app from a template
For sample app, which is used to help user understand App usage scenarios
Use a sample app
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