I'd just like to confirm I've tried this Spaceman program on Windows (with Photo) and it runs fine, but there are a few points to it working:
You need to exit your current Affinity window to "save" your existing layout.
Then run the spaceman.bat (don't run as admin, it doesn't need it)
Save the backup as whatever you like, but it's best not to use spaces. For example, I named mine: affinity-photo-workspace-1
Open Affinity again and if you want to test the backup works, go to Views > Studio > Reset Studio
Run the spaceman.bat again and restore the backup you created
(NB. This doesn't work on MacOS)
Remember that in the same place (probably Downloads) you opened the spaceman.bat and created the backup, there will be a folder called "Workspaces". You need to make sure that is in the same location when you open spaceman.bat to restore the workspace backup (but spaceman.bat shouldn't be in the Workspaces folder)
To keep it simple, I created a folder in Program Files called Affinity Spaceman (like this: C:\Program Files (x86)\Affinity Spaceman), see image: