How does one build an app with iCloud/CloudKit with Unity?

Hi there.

I am building an OSX app that incorporates iCloud, and I am having a ton of trouble trying to test it. I can successfully build it for testing and wrap it with entitlements (thanks to Jemast's Mac App Store Toolset on the Asset Store), but the problem occurs when I try to access iCloud. Although the ubiquityIdentityToken exists (since I'm also using CloudKit), I am getting error messages whenever I try to do anything related to iCloud. Here are some of the errors

-Sandbox: AppName (Number) deny mach-lookup com.apple.cloudd -The CKContainerID is coming back with the error: Domain=NSCocoaErrorDomain Code=4099 "Couldn't communicate with a helper application." (The connection to service named com.apple.cloudd was invalidated.)

So I feel like this issue means that my app can't access iCloud/CloudKit...but I need to be able to access iCloud/CloudKit in order to test the app. If I had access to XCode, this would likely be completely trivial, partially because I already know how to do it for iOS and partially because XCode would set everything up correctly for this to work. I feel like the problem could be related to entitlements or how I'm building the app, but as far as entitlements go, if I do it in another way, I either get the same results or the app crashes on startup with "Code Signature Invalid". I've also tried making an installer package, installing it, and running it, but that always crashes, and from everything I've read, iCloud/CloudKit makes that happen, so that is untestable.

I know other people have made OSX apps that access iCloud using Unity, but it looks like CloudKit doesn't get used much at all with Unity. How do you test iCloud and/or Cloudkit on your OSX apps?

Thanks! I appreciate any help.