If you're getting the "unable to create hooks" error after you click the Create Hooks button, you'll want to check if Waffle is approved as a 3rd party app.
You can go to this link to see if Waffle is listed: https://github.com/settings/connections/applications/b68f04bdff231220a275
If Waffle is approved, you will see the page below and there should be a green checkmark next to the org Waffle is approved for:
If you don't see Waffle listed there, you will you'll need to log out of Waffle and log back in to be prompted to authorize Waffle and create webhooks. (this only applies if you're an owner in your org) If you're not an owner, you'll want to have one do the steps above.