Basic connector SmartApp throws error in SmartThings app

I am having trouble creating a very basic Device Connector SmartApp. I used the following tutorial as a basis: https://smartthings.developer.samsung.com/docs/devices/smartapp/smartapp-connector.html

However the tutorial is outdated and does not run without some code changes (specifically around removing the request verification code included in the example).

After updating the example to the latest version of the NodeJS SmartApp SDK: https://github.com/SmartThingsCommunity/smartapp-sdk-nodejs

I created the Device Connector Smart App, registered it, deployed to test, run my local service and am able to add a Device under ‘My Testing Devices’ in the SmartThings mobile app.

My app handles the various initialization and page events (this is very simple and has one page). The page registration completes, the appasks for me to allow the requested permissions, after I click ‘Allow’ then I get the following error in the app:

I expect to receive an ‘INSTALLED’ lifecycle request that should be picked up by my INSTALL handler.

I dont see any entries in the ‘Live Logging’ feature in the developer workspace so I’m at a loss as to what is happening. Any ideas?

Here’s my connector app source code: https://github.com/mradamlacey/vesync-st-nodejs-web-connector