Start by configure you computer so you can install apps offline:
Then download the zip from:
Unpack this and go inside this dir with either CMD och Terminal then dont forget to issue the command:
npm install --target_arch=arm --target_platform=linux
After that edit app.json and change ID to something else like “myapp.ikea.tradfri.gateway”
also change name to something else so you know which app goes to which gateway like “IKEA Trådfri Gateway 2”
I also changed the id in files package.json and package-lock.json dont know if you have to do that though.
When you are done all you have to issue is “homey app install” and the app will be installed in your homey.
I have alot of lamps and wanted to be able to control all my gateways so this was the solution i came up with (im no developer) until the main app supports multiple gateways.