I just happened to have a chat with Marcel later yesterday and I raised this question.  He suggested running the setup code on a different thread and blocking the UI thread on the completion event once the initialization had proceeded as far as it could go without waiting.

 

I'm still not convinced I understand async sufficiently well, and that perhaps I should be completely restructuring the app initialization as async, but this seems rather drastic, not to mention challenging in a large composite app.

Is it possible to move the query block inside the Coroutine's completed event?

var coop = Coroutine.StartParallel(Tasks);
coop.Completed += (s, args) => {
    //Query the data here
};

 

But, once I'm done with this "other stuff" I mustn't continue with the app until the parallel tasks are completed.  How should I wait (that is, block) at that point?

 

In case you're wondering, the rough working example is loading a bunch of reference data into the EM.  I don't want to query the data in the app until I know its been loaded.  So the plan is to block until it is, having fired off all of the startup tasks and performed other sundry setup (not all of which involving DevForce).