the error shown seems to indicate that you picked the wrong app type

the credentials.json (that you downloaded from google) should look like this

{
  "installed": {     
    "client_id": "cccccc",
    "project_id": "ccccc",
    "auth_uri": "https://accounts.google.com/o/oauth2/auth",
    "token_uri": "https://oauth2.googleapis.com/token",
    "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
    "client_secret": "ccccc",
    "redirect_uris": [
      "http://localhost"
    ]
  }
}

the code is looking for the “installed” item

So there is no many chance to have it working
maybe my EXT plugin can help :)

Well, that didn’t work :(
I have even tried removing the module and creating a whole new thing in google cloud platform as if i was starting from scratch but on each attempt I get the same error

I have no clue what I have done wrong

[GPHOTOS:CORE] TypeError: Cannot read properties of undefined (reading '0')
/home/pi/MagicMirror/modules/MMM-GooglePhotos/GPhotos.js:133
      throw e
      ^

TypeError: Cannot read properties of undefined (reading '0')
    at new Auth (/home/pi/MagicMirror/modules/MMM-GooglePhotos/GPhotos.js:35:91)
    at GPhotos.onAuthReady (/home/pi/MagicMirror/modules/MMM-GooglePhotos/GPhotos.js:130:14)
    at GPhotos.generateToken (/home/pi/MagicMirror/modules/MMM-GooglePhotos/GPhotos.js:141:10)
    at Object.<anonymous> (/home/pi/MagicMirror/modules/MMM-GooglePhotos/generate_token.js:10:9)
    at Module._compile (node:internal/modules/cjs/loader:1105:14)
    at Object.Module._extensions..js (node:internal/modules/cjs/loader:1159:10)
    at Module.load (node:internal/modules/cjs/loader:981:32)
    at Function.Module._load (node:internal/modules/cjs/loader:822:12)
    at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:77:12)
    at node:internal/main/run_main_module:17:47

so from memory that was the token.json with the Auth steps wasnt it? so if I just delete the token and re do that and the Auth, then it should work again? and i wont switch it off this time lol