BizBert

Switching to the old Logic Apps designer from a new Logic App is relatively easy… if you don’t have anything in your logic app! You just need to change the $schema value at the top of your logic app definition.

Here’s an example of how to do it:

1. Create a new Logic App (will open in new designer)
2. Add a manual HTTP Trigger, and a delay action (you need at least one trigger and one action in order to save your Logic App):
   
   
3. Save your Logic App
4. Open your logic app in code view
5. Change the $schema value at the top from:
   "$schema": "https://schema.management.azure.com/providers/Microsoft.Logic/schemas/2015-08-01-preview/workflowdefinition.json#",
   to
   "$schema": "http://schema.management.azure.com/providers/Microsoft.Logic/schemas/2014-12-01-preview/workflowdefinition.json#", (I've highlighted the bits that change)
6. Close your logic app
7. Reopen it - it will open in the old designer (although it will appear to have nothing in it, as the new manual HTTP trigger is not supported) - just add a new trigger and off you go.
   Note: you may need to manually edit the code behind to remove the delay shape - your mileage may vary.

I suspect the product group will release a tool to make this easier.

You can also use this mechanism to go from the old designer to the new one.