Checking whether an application is running can be done using tokens like "{PROCESSEXISTS:}" or "{WINDOWEXISTS:}", E.G. in a condition.
If you want that to happen in the background, you'd need to have a command running a loop (said command could be started when loading the relevant profile, using the "Execute a command each time this profile is loaded" option).
You'd want to structure the command so that whichever actions are to be executed when the application starts only execute once for every time the application is started, of course.
Given that you're referring to a game, which presumably you would be starting manually anyway, an alternate approach could be to start the application through VoiceAttack itself, E.G. using a desktop shortcut containing the "-command" (and perhaps "-profile") option(s) to execute a command that in turn starts the game.