Need help - additional actions like window resizing not triggering

Hi All, firstly this could be (and most likely is) an issue with me and not BTT.....but I do promise I've tried to fix and also searched here and elsewhere to find other possible solutions first.

I'm trying to use BTT to open the Things3 app, with two application windows, each maximised to either left or right & ensure it is displaying on a specific monitor. My aim is to have the window on the left hand side show today and the window on the right upcoming.

The issue I am facing is that the "Attach Additional Actions" involving "Move to Desktop" or "Maximise Left/Right" don't work as additional actions for me.

The following actions work just fine without any issue
Launch Things3.app
Delay next action by 1.70 Seconds
Keyboard shortcut control+command+N (opens a second things window)

Affected input device: Magic Trackpad (three finger double tap)

Device information:

  • Type of Mac: MacBook Pro 2019 13"
  • macOS version: 10.15.4
  • BetterTouchTool version: 3.346

Screen shot of what I'm trying to do in BTT

Screen shot of how I'd like the windows to show up in MacOS

Thanks for any help and pointers you can offer.