Need help setting up SteamVR Input bindings for HTC Vive controllers

Hi all, new to Unreal Engine.

Having a bit of confusion regarding how the Unreal Input Actions bind to the Vive controller inputs.

Using the UE4 VR Template to create a new project, all input works when played within the editor, but when I package a development build to test, the trigger inputs are not bound.

I understand a SteamVRBindings folder which contain various json input binding files is created when I setup a project and that these are pushed to the package build, but in order to get the trigger inputs to work, I have to open up the SteamVR controller bindings UI and assign the ‘GrabLeft’ and ‘GrabRight’ click events to each controller. If I then replace the vive_controller.json with this newly generated json file that SteamVR creates, it all works.

I did notice that I can “regenerate steamvr bindings” within the editor, but this does not fix the trigger issue.

My question is about workflow, should the default json input bindings setup by the UE4 editor work out of the box, or do I need to perform a first time setup when I package my project and assign the bindings through the SteamVR controller input UI. If so how does the work when I finally Package my project for distribution. Should I edit these files manually within my project directory?

If anyone can clarify this would be gratefully appreciated.

I’m using Unreal Engine 4.25.3 market build.