ProjectServerManager.GetProjectRawData

public Stream GetProjectRawData(Guid projectGuid)

In this example the debug info for the specific project is retrieved. You can pass the resulting "debug.zip" to the support team for troubleshooting purposes.
[C#]
var credentials = new ProjectServerCredentials("https://xxxxxx.sharepoint.com", "yyyyy@xxxxxxx.onmicrosoft.com", "contraseña");
// GUID del proyecto que está tratando de obtener.
var projectGuid = new Guid("e0294bfb-5657-45c8-9cc5-82169fb95d69");
ProjectServerManager manager = new ProjectServerManager(credentials);
using (var fileStream = File.OpenWrite(@"c:\debug.zip"))
{
    using (var stream = manager.GetProjectRawData(projectGuid))
    {
        stream.CopyTo(fileStream);
    }
}