Windowed game being copied to all desktops

[tbhuang2]

I play a game (Team Fortress 2) in windowed mode, which I start in Desktop 4. I would like it to only be in Desktop 4. However when I start the game, it is automatically copied to all of my other desktops.
I want to avoid making a rule because sometimes I run the game in windowed mode, and I want it to be in Desktop 4 only. Other times I play the game in full screen mode, and I want it in Desktop 1. So, I don't think it is possible to separate these cases into rules.
Is there a way to stop the game from being copied to all desktops when it starts?

[Patrick]

A move exception in the wechsel.ini might work.