1) No, this module can't tell you whether the box is on or not - it's very much a one way street - you can send commands to the box but there is no feedback at all from the box about its status or whether it could perform the command. All you can tell is whether you managed to send the command or not. Its pretty much like a real life Sky remote control in that respect. To know whether the box is on or not, would need to do some stuff the other module was doing I suspect (they are completely different in how the communicate with the box)
2) I'm not sure about the Sky button, to be honest I'm not sure if I tried using it. The TV button shouldn't be in the code at all - I need to remove it. If you think about it, your sky box cannot control your TV - which is why there are no codes for volume buttons either.