Foundation model adapter assets are invalid

I've tried creating a Lora adapter using the example dataset, scripts as part of the adapter_training_toolkit_v26_0_0 (last available) on MacOs 26 Beta 6.

import SwiftUI
import FoundationModels
import Playgrounds



#Playground {
    
    // The absolute path to your adapter.
    let localURL = URL(filePath: "/Users/syl/Downloads/adapter_training_toolkit_v26_0_0/train/test-lora.fmadapter")


    // Initialize the adapter by using the local URL.
    let adapter = try SystemLanguageModel.Adapter(fileURL: localURL)
    
    // An instance of the the system language model using your adapter.
    let customAdapterModel = SystemLanguageModel(adapter: adapter)


    // Create a session and prompt the model.
    let session = LanguageModelSession(model: customAdapterModel)
    let response = try await session.respond(to: "hello")
}

I get Adapter assets are invalid error.

I've added the entitlements

Is adapter_training_toolkit_v26_0_0 up to date?