In case you haven't found a solution, you could try using SendPlay, or set the script to have administrator access:
On Windows Vista, some scripts might require administrator privileges to function properly (such as a script that interacts with a process or window that is run as administrator). To achieve this, add the following at the top of the script (this would need to be enhanced to work for compiled scripts and/or to pass parameters):
Code:
if not A_IsAdmin
{
DllCall("shell32\ShellExecuteA", uint, 0, str, "RunAs", str, A_AhkPath
, str, """" . A_ScriptFullPath . """", str, A_WorkingDir, int, 1)
ExitApp
}