Problem getting Test Clock to work with Inline Forms vs Hosted

I am stumped with how to get the test clock in the sandbox to work.  I can get the transactions to show up registed, paid, and subscribed if in the Gateway settings, I select Hosted (Checkout) but then the Test Clock will not work with that setting. It shows as set to "Null'.  If I select Inline Forms (Elements), the transaction remains in pending status in CBSubs/Payments. 
I am hoping you can let me know the steps to take to resolve this situation so I can test future payments with the Test Clock.
Thank you in advance for any help you can provide.
Chris

You cannot use test clocks with hosted checkout. Switch back to inline elements. Once you've done so when you go to subscribe the payment area where you normally input credit card details will just have a button to pay with a test clock. Test clocks don't immediately activate. They generate an invoice that is paid out and CBSubs will handle the webhook sent by that payment. So if you do not have webhooks properly configured CBSubs will never be notified of payments. Webhook configuration instructions are included in the CBSubs Stripe gateway configuration. You can then advance a test clock within your Stripe account to pass time on the subscription.

Thank you Krileon. I am pretty certain the webhook is properly configured since i checed it several times yesterday in getting the sandbox to work. I'll check again. Is there a transaction i should see that would tell me how far the registration made it befor stalling out?
Many thanks for the quick reply, greatly appreciated.
Chris

Your test clock should immediately exist in your Stripe account and the subscription as well. It won't stall out. It'll just exist and retry webhooks if the webhooks failed for whatever reason. We respond to all of Stripes webhooks with a response message so the webhook log should also show return messages.

Test Clocks are solely for the purpose of testing recurring subscriptions. You do not need them for regular test payments nor will they work for regular test payments. They only work for recurring subscriptions.

There's no real complicated process here. It's a simple matter of just pressing the button and advancing the clock from Stripe. Below is a step by step.

1. Plan Selection
 
2. Basket
 
3. Payment
 
4. Confirmation
 
5. Stripe Subscriptions
 
6. Stripe Test Clocks (Simulations)
 
7. Stripe Test Clock (Simulation)
 

Step 7 is where you'd advance time on the subscription to see how renewals would behavior. That's basically the only purpose to using test clocks. Additional details below.

Notification Log
 

Everything tracked exactly as shown, but the status still remains Pending.  I double-checked the webhook destination, signing secret, published and secret keys, and they all match. I'm hoping you can help me figure out what's wrong. They say, "You have to be smarter than the gear you are trying to use," and I am clearly failing that test. I really hate to ask for more help because you've done such a great job helping, but would I be crazy to see if you could help a bit more?
Thank you,
Chris