Hello Gaby,
You will not be able to set the CreatedBy field - it will be populated with the user that was used when logging your application in (integration user).
As for populating the Project Manager field, try this:
{
"entity": {
"Id": "/Project",
"Name": "New Project Try 6",
"StartDate": "2019-11-01",
"DueDate": "2019-12-01",
"PlannedBudget":30,
"ProjectManager": "/User/ExternalId"
}
}
ExternalId needs to be replaced with an actual External ID that can be found in user properties. Example:
I hope this helps.
Roland