For Enabled the program, the syntax is Program.Run("ID or NAME");
For Desabled, there is the command Stop() but you have to get the pointer of the program, I don't find a command as Run(), or you have to set a parameter that is read by your program.
Or Yes as bkenoki says, the virtual switch is attach to your program as I preconise to igorbertifoc for squeezebox (Sources on APP CONTRIBUTION)
Cheers
Dani