I use KM to open multiple apps, but they are all opened in Desktop 1. I have 6 desktop spaces, 1 each for Video editing, Image Editing, Source code, Browsing and so on..
Using KM how can I assign each application to a specific Desktop space. Say, assign Photoshop to Desktop 2 ?
Did you check the threads on this website that deal with Spaces, like this one:
Hi, @JJohn. If you want to assign an app to a specific Desktop Space, Keyboard Maestro is not required. Just follow these steps:
If the app is open, quit it.
Navigate to the desired Desktop Space.
Open the app.
Right-click on the app icon in the dock and select This Desktop.
Now if you want more versatility with navigation and window movement between Desktop Spaces, check out the thread that @Airy suggested. 
@_jims Thanks for the reply.
Actually, I had seen this [Unanswered] post from 2020 on this forum earlier. Move Application Windows to Named Desktop/Space
The OP had mentioned this problem in that Post
I too had this problem where apps move to wrong spaces if they are told to move to specific desktop spaces by the technique @_jims suggested. So I thought there was a solution for this using KM in 2024.
[Edit] Found out from this thread that @Airy posted above that Mission control automatically re-arranges spaces based on use. Seems that was causing the problem of apps opening in the wrong workspace.
For the benefit of others that might subsequently see this thread…
Disable this setting: Automatically rearrange Spaces based on most recent use
In the thread that @Airy mentioned above (one I started) you will find that guidance and other recommendations.
